FORM 2
THE PATENTS ACT, 1970
(39 of 1970)
AND
THE PATENTS RULES, 2003
COMPLETE
SPECIFICATION
(See Section 10; Rule 13)
CATALYSTS
ECONIC TECHNOLOGIES LTD
a British Company of,
Level 1 Bessemer Building
Imperial College London SW7 2AZ,
Great Britain
THE FOLLOWING SPECIFICATION PARTICULARLY DESCRIBES THE
INVENTION AND THE MANNER IN WHICH IT IS TO BE PERFORMED.
2
FIELD OF THE INVENTION
The present invention relates to the field of polymerisation catalysts, and
systems comprising said catalysts for polymerising carbon dioxide and an
epoxide, a lactide and/or lactone, and/or an epoxide and an anhydride.
5
BACKGROUND
Environmental and economic concerns associated with depleting oil resources
have triggered a growing interest in the chemical conversion of carbon dioxide
(CO2), so as to enable its use as a renewable carbon source. CO2 is, despite its
10 low reactivity, a highly attractive carbon feedstock, as it is inexpensive, virtually
non-toxic, abundantly available in high purity and non-hazardous. Therefore,
CO2 could be a promising substitute for substances such as carbon monoxide,
phosgene or other petrochemical feedstocks in many processes. One of the
developing applications of CO2 is copolymerization with epoxides to yield
15 aliphatic polycarbonates. The development of effective catalysts to make such a
process profitable is the subject of continuous research.
In WO2009/130470, the contents of which are incorporated herein by reference
in their entirety, the copolymerisation of an epoxide with CO2 using a catalyst of
20 a class represented by formula (I) was described:
E1
R1
N
R4
E2
R4N
E1
R1
R4
N
NR4
E2
M M
X
X
R3 R3
R2 R2
R2 R2
(I)
WO2013/034750, the contents of which are incorporated herein by reference in
25 their entirety, discloses the copolymerisation of an epoxide with CO2 in the
3
presence of a chain transfer agent using a catalyst of a class represented by
formula (II):
(II)
5 Various compounds according to formulae (I) and (II) above were tested for their
ability to catalyse the reaction between different epoxides and carbon dioxide. In
both WO2009/130470 and WO2013/034750, M is specified as being selected
from Zn(II), Cr(II), Co(II), Mn(II), Mg(II), Fe(II), Ti(II), Cr(III)-X, Co(III)-X, Mn(III)-X,
Fe(III)-X, Ca(II), Ge(II), Al(III)-X, Ti(III)-X, V(III)-X, Ge(IV)-(X)2 or Ti(IV)-(X)2.
10
Among the epoxides employed in the copolymerization reactions of the prior art,
cyclohexene oxide (CHO) received special interest, as the product,
poly(cyclohexene carbonate) (PCHC) shows a high glass transition temperature
and reasonable tensile strength. Ethylene oxide, propylene oxide and butylene
15 oxide have also received interest as they produce polymers (polyalkylene
carbonates, such as PPC) with elastomeric properties which are useful in many
applications e.g. films.
WO2012/037282 discloses a catalyst of formula:
20
WO2012/037282 indicates that these compounds may be useful for the
copolymerisation of an epoxide with CO2. WO2012/037282 states that M1 and
4
M2 can be any metal atom. However, these complexes were not tested to
determine which if any possessed the necessary catalytic activity.
5
The inventors have now surprisingly found that bimetallic catalysts having at
least one nickel metal centre, are active as polymerisation catalysts. In
particular, the inventors have found that bimetallic catalysts having at least one
nickel metal centre, and preferably having two nickel metal centres, are better in
10 terms of activity and/or selectivity than the catalysts previously disclosed in the
art. In particular, catalysts of the invention have improved activity in relation to disubstituted
meso-epoxides (e.g. cyclohexene oxide) and mono-substituted
epoxides (e.g.propylene oxide), and furthermore improved selectivity to monosubstituted
epoxides.
15
SUMMARY OF THE INVENTION
According to a first aspect of the present invention, there is provided a catalyst of
formula (I):
(I)
20 wherein:
5
M1 and M2 are independently selected from Zn(II), Cr(II), Co(II), Cu(II), Mn(II),
Mg(II), Ni(II), Fe(II), Ti(II), V(II), Cr(III)-X, Co(III)-X, Mn(III)-X, Ni(III)-X, Fe(III)-X,
Ca(II), Ge(II), Al(III)-X, Ti(III)-X, V(III)-X, Ge(IV)-(X)2 or Ti(IV)-(X)2;
wherein at least one of M1 or M2 is selected from Ni(II), and Ni(III)-X;
5 R1 and R2 are independently selected from hydrogen, halide, a nitro group, a
nitrile group, an imine, an amine, an ether group, a silyl group, a silyl ether
group, a sulfoxide group, a sulfonyl group, a sulfinate group or an acetylide
group or an optionally substituted alkyl, alkenyl, alkynyl, haloalkyl, aryl,
heteroaryl, alkoxy, aryloxy, alkylthio, arylthio, alicyclic or heteroalicyclic group;
10 R3 is independently selected from optionally substituted alkylene, alkenylene,
alkynylene, heteroalkylene, heteroalkenylene, heteroalkynylene, arylene,
heteroarylene or cycloalkylene, wherein alkylene, alkenylene, alkynylene,
heteroalkylene, heteroalkenylene and heteroalkynylene, may optionally be
interrupted by aryl, heteroaryl, alicyclic or heteroalicyclic;
15 R5 is independently selected from H, or optionally substituted aliphatic,
heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl, alkylheteroaryl or
alkylaryl;
E1 is C, E2 is O, S or NH or E1 is N and E2 is O;
E3, E4, E5 and E6 are selected from N, NR4, O and S, wherein when E3, E4,
20 E5 or E6 are N, is , and wherein when E3, E4, E5 or E6 are NR4,
O or S, is ; R4 is independently selected from H, or optionally
substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl,
alkylheteroaryl or alkylaryl;
25 X is independently selected from OC(O)Rx, OSO2Rx, OSORx, OSO(Rx)2,
S(O)Rx, ORx, phosphinate, halide, nitrate, hydroxyl, carbonate, amino, nitro,
amido or optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic,
aryl or heteroaryl;
Rx is independently hydrogen, or optionally substituted aliphatic, haloaliphatic,
30 heteroaliphatic, alicyclic, heteroalicyclic, aryl, alkylaryl or heteroaryl; and
G is absent or independently selected from a neutral or anionic donor ligand
which is a Lewis base.
6
In a second aspect of the invention, there is provided a process for the reaction
of (i) carbon dioxide with an epoxide, (ii) an anhydride and an epoxide, and/or
(iii) a lactide and/or a lactone in the presence of a catalyst according to the first
aspect, optionally in the presence of a chain transfer agent.
5
The third aspect of the invention provides a product of the process of the second
aspect of the invention.
In a further aspect, the invention extends to methods of preparation of ligands,
10 complexes and catalysts according to the first aspect and/or as defined herein.
DEFINITIONS
For the purpose of the present invention, an aliphatic group is a hydrocarbon
moiety that may be straight chain or branched and may be completely saturated,
15 or contain one or more units of unsaturation, but which is not aromatic. The term
“unsaturated” means a moiety that has one or more double and/or triple bonds.
The term “aliphatic” is therefore intended to encompass alkyl, alkenyl or alkynyl
groups, and combinations thereof. An aliphatic group is preferably a C1-
20aliphatic group, that is, an aliphatic group with 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11,
20 12, 13, 14, 15, 16, 17, 18, 19 or 20 carbon atoms. Preferably, an aliphatic group
is a C1-15aliphatic, more preferably a C1-12aliphatic, more preferably a C1-
10aliphatic, even more preferably a C1-8aliphatic, such as a C1-6aliphatic group.
An alkyl group is preferably a “C1-20 alkyl group”, that is an alkyl group that is a
25 straight or branched chain with 1 to 20 carbons. The alkyl group therefore has 1,
2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 carbon atoms.
Preferably, an alkyl group is a C1-15alkyl, preferably a C1-12alkyl, more preferably
a C1-10alkyl, even more preferably a C1-8alkyl, even more preferably a C1-6alkyl
group. Specifically, examples of “C1-20 alkyl group“ include methyl group, ethyl
30 group, n-propyl group, iso-propyl group, n-butyl group, iso-butyl group, sec-butyl
group, tert-butyl group, n-pentyl group, n-hexyl group, n-heptyl group, n-octyl
group, n-nonyl group, n-decyl group, n-undecyl group, n-dodecyl group, ntridecyl
group, n-tetradecyl group, n-pentadecyl group, n-hexadecyl group, n-
7
heptadecyl group, n-octadecyl group, n-nonadecyl group, n-eicosyl group, 1,1-
dimethylpropyl group, 1,2-dimethylpropyl group, 2,2-dimethylpropyl group, 1-
ethylpropyl group, n-hexyl group, 1-ethyl-2-methylpropyl group, 1,1,2-
trimethylpropyl group, 1-ethylbutyl group, 1-methylbutyl group, 2-methylbutyl
5 group, 1,1-dimethylbutyl group, 1,2-dimethylbutyl group, 2,2-dimethylbutyl group,
1,3-dimethylbutyl group, 2,3-dimethylbutyl group, 2-ethylbutyl group, 2-
methylpentyl group, 3-methylpentyl group and the like.
Alkenyl and alkynyl groups are preferably “C2-20alkenyl” and “C2-20alkynyl”, more
10 preferably “C2-15alkenyl” and “C2-15alkynyl”, even more preferably “C2-12alkenyl”
and “C2-12alkynyl”, even more preferably “C2-10alkenyl” and “C2-10alkynyl”, even
more preferably “C2-8alkenyl” and “C2-8alkynyl”, most preferably “C2-6alkenyl” and
“C2-6alkynyl” groups, respectively.
15 A heteroaliphatic group (including heteroalkyl, heteroalkenyl and heteroalkynyl)
is an aliphatic group as described above, which additionally contains one or
more heteroatoms. Heteroaliphatic groups therefore preferably contain from 2 to
21 atoms, preferably from 2 to 16 atoms, more preferably from 2 to 13 atoms,
more preferably from 2 to 11 atoms, more preferably from 2 to 9 atoms, even
20 more preferably from 2 to 7 atoms, wherein at least one atom is a carbon atom.
Particularly preferred heteroatoms are selected from O, S, N, P and Si. When
heteroaliphatic groups have two or more heteroatoms, the heteroatoms may be
the same or different.
25 An alicyclic group is a saturated or partially unsaturated cyclic aliphatic
monocyclic or polycyclic (including fused, bridging and spiro-fused) ring system
which has from 3 to 20 carbon atoms, that is an alicyclic group with 3, 4, 5, 6, 7,
8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19 or 20 carbon atoms. Preferably, an
alicyclic group has from 3 to 15, more preferably from 3 to 12, even more
30 preferably from 3 to 10, even more preferably from 3 to 8 carbon atoms, even
more preferably from 3 to 6 carbons atoms. The term “alicyclic” encompasses
cycloalkyl, cycloalkenyl and cycloalkynyl groups. It will be appreciated that the
alicyclic group may comprise an alicyclic ring bearing one or more linking or non-
8
linking alkyl substituents, such as –CH2-cyclohexyl. Specifically, examples of the
C3-20 cycloalkyl group include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl,
cycloheptyl, adamantyl and cyclooctyl.
5 A heteroalicyclic group is an alicyclic group as defined above which has, in
addition to carbon atoms, one or more ring heteroatoms, which are preferably
selected from O, S, N, P and Si. Heteroalicyclic groups preferably contain from
one to four heteroatoms, which may be the same or different. Heteroalicyclic
groups preferably contain from 5 to 20 atoms, more preferably from 5 to 14
10 atoms, even more preferably from 5 to 12 atoms.
An aryl group is a monocyclic or polycyclic ring system having from 5 to 20
carbon atoms. An aryl group is preferably a “C6-12 aryl group” and is an aryl
group constituted by 6, 7, 8, 9, 10, 11 or 12 carbon atoms and includes
15 condensed ring groups such as monocyclic ring group, or bicyclic ring group and
the like. Specifically, examples of “C6-10 aryl group” include phenyl group,
biphenyl group, indenyl group, naphthyl group or azulenyl group and the like. It
should be noted that condensed rings such as indan and tetrahydro naphthalene
are also included in the aryl group.
20
A heteroaryl group is an aryl group having, in addition to carbon atoms, from one
to four ring heteroatoms which are preferably selected from O, S, N, P and Si. A
heteroaryl group preferably has from 5 to 20, more preferably from 5 to 14 ring
atoms. Specifically, examples of a heteroaryl group include pyridine, imidazole,
25 methylimidazole and dimethylaminopyridine.
Examples of alicyclic, heteroalicyclic, aryl and heteroaryl groups include but are
not limited to cyclohexyl, phenyl, acridine, benzimidazole, benzofuran,
benzothiophene, benzoxazole, benzothiazole, carbazole, cinnoline, dioxin,
30 dioxane, dioxolane, dithiane, dithiazine, dithiazole, dithiolane, furan, imidazole,
imidazoline, imidazolidine, indole, indoline, indolizine, indazole, isoindole,
isoquinoline, isoxazole, isothiazole, morpholine, napthyridine, oxazole,
oxadiazole, oxathiazole, oxathiazolidine, oxazine, oxadiazine, phenazine,
9
phenothiazine, phenoxazine, phthalazine, piperazine, piperidine, pteridine,
purine, pyran, pyrazine, pyrazole, pyrazoline, pyrazolidine, pyridazine, pyridine,
pyrimidine, pyrrole, pyrrolidine, pyrroline, quinoline, quinoxaline, quinazoline,
quinolizine, tetrahydrofuran, tetrazine, tetrazole, thiophene, thiadiazine,
5 thiadiazole, thiatriazole, thiazine, thiazole, thiomorpholine, thianaphthalene,
thiopyran, triazine, triazole, and trithiane.
The term “halide” or “halogen” are used interchangeably and, as used herein
mean a fluorine atom, a chlorine atom, a bromine atom, an iodine atom and the
10 like, preferably a fluorine atom, a bromine atom or a chlorine atom, and more
preferably a fluorine atom.
A haloalkyl group is preferably a “C1-20 haloalkyl group”, more preferably a “C1-15
haloalkyl group”, more preferably a “C1-12 haloalkyl group”, more preferably a “C1-
15 10 haloalkyl group”, even more preferably a “C1-8 haloalkyl group”, even more
preferably a “C1-6 haloalkyl group” and is a C1-20 alkyl, a C1-15 alkyl, a C1-12 alkyl,
a C1-10 alkyl, a C1-8 alkyl, or a C1-6 alkyl group, respectively, as described above
substituted with at least one halogen atom, preferably 1, 2 or 3 halogen atom(s).
Specifically, examples of “C1-20 haloalkyl group” include fluoromethyl group,
20 difluoromethyl group, trifluoromethyl group, fluoroethyl group, difluroethyl group,
trifluoroethyl group, chloromethyl group, bromomethyl group, iodomethyl group
and the like.
An alkoxy group is preferably a “C1-20 alkoxy group”, more preferably a “C1-15
25 alkoxy group”, more preferably a “C1-12 alkoxy group”, more preferably a “C1-10
alkoxy group”, even more preferably a “C1-8 alkoxy group”, even more preferably
a “C1-6 alkoxy group” and is an oxy group that is bonded to the previously
defined C1-20 alkyl, C1-15 alkyl, C1-12 alkyl, C1-10 alkyl, C1-8 alkyl, or C1-6 alkyl group
respectively. Specifically, examples of “C1-20 alkoxy group” include methoxy
30 group, ethoxy group, n-propoxy group, iso-propoxy group, n-butoxy group, isobutoxy
group, sec-butoxy group, tert-butoxy group, n-pentyloxy group, isopentyloxy
group, sec-pentyloxy group, n-hexyloxy group, iso-hexyloxy group, , nhexyloxy
group, n-heptyloxy group, n-octyloxy group, n-nonyloxy group, n-
10
decyloxy group, n-undecyloxy group, n-dodecyloxy group, n-tridecyloxy group, ntetradecyloxy
group, n-pentadecyloxy group, n-hexadecyloxy group, nheptadecyloxy
group, n-octadecyloxy group, n-nonadecyloxy group, n-eicosyloxy
group, 1,1-dimethylpropoxy group, 1,2-dimethylpropoxy group, 2,2-
5 dimethylpropoxy group, 2-methylbutoxy group, 1-ethyl-2-methylpropoxy group,
1,1,2-trimethylpropoxy group, 1,1-dimethylbutoxy group, 1,2-dimethylbutoxy
group, 2,2-dimethylbutoxy group, 2,3-dimethylbutoxy group, 1,3-dimethylbutoxy
group, 2-ethylbutoxy group, 2-methylpentyloxy group, 3-methylpentyloxy group
and the like.
10
An aryloxy group is preferably a “C5-20 aryloxy group”, more preferably a “C6-12
aryloxy group”, even more preferably a “C6-10 aryloxy group” and is an oxy group
that is bonded to the previously defined C5-20 aryl, C6-12 aryl, or C6-10 aryl group
respectively.
15
An alkylthio group is preferably a “C1-20 alkylthio group”, more preferably a “C1-15
alkylthio group”, more preferably a “C1-12 alkylthio group”, more preferably a “C1-
10 alkylthio group”, even more preferably a “C1-8 alkylthio group”, even more
preferably a “C1-6 alkylthio group” and is a thio (-S-) group that is bonded to the
20 previously defined C1-20 alkyl, C1-15 alkyl, C1-12 alkyl, C1-10 alkyl, C1-8 alkyl, or C1-6
alkyl group respectively.
An arylthio group is preferably a “C5-20 arylthio group”, more preferably a “C6-12
arylthio group”, even more preferably a “C6-10 arylthio group” and is an thio (-S-)
25 group that is bonded to the previously defined C5-20 aryl, C6-12 aryl, or C6-10 aryl
group respectively.
An alkylaryl group is preferably a “C6-12 aryl C1-20 alkyl group”, more preferably a
preferably a “C6-12 aryl C1-16 alkyl group”, even more preferably a “C6-12 aryl C1-6
30 alkyl group” and is an aryl group as defined above bonded at any position to an
alkyl group as defined above. The point of attachment of the alkylaryl group to a
molecule may be via the alkyl portion and thus, preferably, the alkylaryl group is -
CH2-Ph or -CH2CH2-Ph. An alkylaryl group can also be referred to as “aralkyl”.
11
A silyl group is preferably a group –Si(Rs)3, wherein each Rs can be
independently an aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl or
heteroaryl group as defined above. In certain embodiments, each Rs is
independently an unsubstituted aliphatic, alicyclic or aryl. Preferably, each Rs is
5 an alkyl group selected from methyl, ethyl or propyl.
A silyl ether group is preferably a group OSi(R6)3 wherein each R6 can be
independently an aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl or
heteroaryl group as defined above. In certain embodiments, each R6 can be
10 independently an unsubstituted aliphatic, alicyclic or aryl. Preferably, each R6 is
an optionally substituted phenyl or optionally substituted alkyl group selected
from methyl, ethyl, propyl or butyl (such as n-butyl or tert-butyl (tBu)). Exemplary
silyl ether groups include OSi(Me)3, OSi(Et)3, OSi(Ph)3, OSi(Me)2(tBu), OSi(tBu)3
and OSi(Ph)2(tBu).
15
A nitrile group (also referred to as a cyano group) is a group CN.
An imine group is a group –CRNR, preferably a group –CHNR7 wherein R7 is an
aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl or heteroaryl group as
20 defined above. In certain embodiments, R7 is unsubstituted aliphatic, alicyclic or
aryl. Preferably R7 is an alkyl group selected from methyl, ethyl or propyl.
An acetylide group contains a triple bond -C≡C-R9, preferably wherein R9 can be
hydrogen, an aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl or heteroaryl
25 group as defined above. For the purposes of the invention when R9 is alkyl, the
triple bond can be present at any position along the alkyl chain. In certain
embodiments, R9 is unsubstituted aliphatic, alicyclic or aryl. Preferably R9 is
methyl, ethyl, propyl or phenyl.
30 An amino group is preferably -NH2, -NHR10 or -N(R10)2 wherein R10 can be an
aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, a silyl group, aryl or heteroaryl
group as defined above. It will be appreciated that when the amino group is
N(R10)2, each R10 group can be the same or different. In certain embodiments,
12
each R10 is independently an unsubstituted aliphatic, alicyclic, silyl or aryl.
Preferably R10 is methyl, ethyl, propyl, SiMe3 or phenyl.
An amido group is preferably –NR11C(O)- or –C(O)-NR11- wherein R11 can be
5 hydrogen, an aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl or heteroaryl
group as defined above. In certain embodiments, R11 is unsubstituted aliphatic,
alicyclic or aryl. Preferably R11 is hydrogen, methyl, ethyl, propyl or phenyl. The
amido group may be terminated by hydrogen, an aliphatic, heteroaliphatic,
alicyclic, heteroalicyclic, aryl or heteroaryl group.
10
An ester group is preferably –OC(O)R12- or –C(O)OR12- wherein R12 can be
hydrogen, an aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl or heteroaryl
group as defined above. In certain embodiments, R12 is unsubstituted aliphatic,
alicyclic or aryl. Preferably R12 is hydrogen, methyl, ethyl, propyl or phenyl. The
15 ester group may be terminated by hydrogen, an aliphatic, heteroaliphatic,
alicyclic, heteroalicyclic, aryl or heteroaryl group.
A sulfoxide is preferably –S(O)R13 and a sulfonyl group is preferably –S(O)2R13
wherein R13 can be hydrogen, an aliphatic, heteroaliphatic, alicyclic,
20 heteroalicyclic, aryl or heteroaryl group as defined above. In certain
embodiments, R13 is unsubstituted aliphatic, alicyclic or aryl. Preferably R13 is
hydrogen, methyl, ethyl, propyl or phenyl.
A carboxylate group is preferably -OC(O)R14, wherein R14 can be hydrogen, an
25 aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl or heteroaryl group as
defined above. In certain embodiments, R14 is unsubstituted aliphatic, alicyclic or
aryl. Preferably R14 is hydrogen, methyl, ethyl, propyl, butyl (for example n-butyl,
isobutyl or tert-butyl), phenyl, pentafluorophenyl, pentyl, hexyl, heptyl, octyl,
nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl, hexadecyl,
30 heptadecyl, octadecyl, nonadecyl, eicosyl, trifluoromethyl or adamantyl.
An acetamide is preferably MeC(O)N(R15)2 wherein R15 can be hydrogen, an
aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl or heteroaryl group as
13
defined above. In certain embodiments, R15 is unsubstituted aliphatic, alicyclic or
aryl. Preferably R15 is hydrogen, methyl, ethyl, propyl or phenyl.
A phosphinate group is preferably a group –OP(O)(R16)2 or –P(O)(OR16) wherein
5 each R16 is independently selected from hydrogen, or an aliphatic,
heteroaliphatic, alicyclic, heteroalicyclic, aryl or heteroaryl group as defined
above. In certain embodiments, R16 is aliphatic, alicyclic or aryl, which are
optionally substituted by aliphatic, alicyclic, aryl or C1-6alkoxy. Preferably R16 is
optionally substituted aryl or C1-20 alkyl, more preferably phenyl optionally
10 substituted by C1-6alkoxy (preferably methoxy) or unsubstituted C1-20alkyl (such
as hexyl, octyl, decyl, dodecyl, tetradecyl, hexadecyl, stearyl).
A sulfinate group is preferably –OSOR17 wherein R17 can be hydrogen, an
aliphatic, heteroaliphatic, haloaliphatic, alicyclic, heteroalicyclic, aryl or heteroaryl
15 group as defined above. In certain embodiments, R17 is unsubstituted aliphatic,
alicyclic or aryl. Preferably R17 is hydrogen, methyl, ethyl, propyl or phenyl.
A carbonate group is preferably OC(O)OR18, wherein R18 can be hydrogen, an
aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl or heteroaryl group as
20 defined above. In certain embodiments, R18 is optionally substituted aliphatic,
alicyclic or aryl. Preferably R18 is hydrogen, methyl, ethyl, propyl, butyl (for
example n-butyl, isobutyl or tert-butyl), phenyl, pentafluorophenyl, pentyl, hexyl,
heptyl, octyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, pentadecyl,
hexadecyl, heptadecyl, octadecyl, nonadecyl, eicosyl, trifluoromethyl, cyclohexyl,
25 benzyl or adamantyl.
It will be appreciated that where any of the above groups are present in a Lewis
base G, one or more additional R groups may be present, as appropriate, to
complete the valency. For example, in the context of an amino group, an
30 additional R group may be present to give RNHR10., wherein R is hydrogen, an
optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl or
heteroaryl group as defined above. Preferably, R is hydrogen or aliphatic,
alicyclic or aryl.
14
Any of the aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl,
haloalkyl, alkoxy, aryloxy, alkylthio, arylthio, alkylaryl, silyl, silyl ether, ester,
sulfoxide, sulfonyl, carboxylate, carbonate, imine, acetylide, amino, phosphinate,
sulfonate or amido groups wherever mentioned in the definitions above, may
5 optionally be substituted by halogen, hydroxy, nitro, carboxylate, carbonate,
alkoxy, aryloxy, alkylthio, arylthio, heteroaryloxy, alkylaryl, amino, amido, imine,
nitrile, silyl, silyl ether, ester, sulfoxide, sulfonyl, acetylide, phosphinate, sulfonate
or optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl or
heteroaryl groups (for example, optionally substituted by halogen, hydroxy, nitro,
10 carbonate, alkoxy, aryloxy, alkylthio, arylthio, amino, imine, nitrile, silyl, sulfoxide,
sulfonyl, phosphinate, sulfonate or acetylide).
It will be appreciated that although in formula (I), the groups X and G are
illustrated as being associated with a single M1 or M2 metal centre, one or more
15 X and G groups may form a bridge between the M1 and M2 metal centres.
For the purposes of the present invention, the epoxide substrate is not limited.
The term epoxide therefore relates to any compound comprising an epoxide
moiety. Examples of epoxides which may be used in the present invention
20 include, but are not limited to, cyclohexene oxide, styrene oxide, propylene
oxide, butylene oxide, substituted cyclohexene oxides (such as limonene oxide,
C10H16O or 2-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, C11H22O), alkylene
oxides (such as ethylene oxide and substituted ethylene oxides), unsubstituted
or substituted oxiranes (such as oxirane, epichlorohydrin, 2-(2-
25 methoxyethoxy)methyl oxirane (MEMO), 2-(2-(2-methoxyethoxy)ethoxy)methyl
oxirane (ME2MO), 2-(2-(2-(2-methoxyethoxy)ethoxy)ethoxy)methyl oxirane
(ME3MO), 1,2-epoxybutane, glycidyl ethers, vinyl-cyclohexene oxide, 3-phenyl-
1,2-epoxypropane, 1,2- and 2,3-epoxybutane, isobutylene oxide, cyclopentene
oxide, 2,3-epoxy-1,2,3,4-tetrahydronaphthalene, indene oxide, and
30 functionalized 3,5-dioxaepoxides. Examples of functionalized 3,5-dioxaepoxides
include:
15
.
The epoxide moiety may be a glycidyl ether, glycidyl ester or glycidyl carbonate.
Examples of glycidyl ethers, glycidyl esters glycidyl carbonates include:
5 .
The epoxide substrate may contain more than one epoxide moiety, i.e. it may be
a bis-epoxide, a tris-epoxide, or a multi-epoxide containing moiety. Examples of
compounds including more than one epoxide moiety include bisphenol A
16
diglycidyl ether and 3,4-epoxycyclohexylmethyl 3,4-
epoxycyclohexanecarboxylate. It will be understood that reactions carried out in
the presence of one or more compounds having more than one epoxide moiety
may lead to cross-linking in the resulting polymer.
5
The skilled person will appreciate that the epoxide can be obtained from “green”
or renewable resources. The epoxide may be obtained from a (poly)unsaturated
compound, such as those deriving from a fatty acid and/or terpene, obtained
using standard oxidation chemistries.
10
The epoxide moiety may contain –OH moieties, or protected –OH moieties. The
–OH moieties may be protected by any suitable protecting group. Suitable
protecting groups include methyl or other alkyl groups, benzyl, allyl, tert-butyl,
tetrahydropyranyl (THP), methoxymethyl (MOM), acetyl (C(O)alkyl), benzolyl
15 (C(O)Ph), dimethoxytrityl (DMT), methoxyethoxymethyl (MEM), p-methoxybenzyl
(PMB), trityl, silyl (such as trimethylsilyl (TMS), t-Butyldimethylsilyl (TBDMS), tButyldiphenylsilyl
(TBDPS), tri-iso-propylsilyloxymethyl (TOM), and
triisopropylsilyl (TIPS)), (4-methoxyphenyl)diphenylmethyl (MMT),
tetrahydrofuranyl (THF), and tetrahydropyranyl (THP).
20
The epoxide preferably has a purity of at least 98%, more preferably >99%.
It will be understood that the term “an epoxide” is intended to encompass one or
more epoxides. In other words, the term “an epoxide” refers to a single epoxide,
25 or a mixture of two or more different epoxides. For example, the epoxide
substrate may be a mixture of ethylene oxide and propylene oxide, a mixture of
cyclohexene oxide and propylene oxide, a mixture of ethylene oxide and
cyclohexene oxide, or a mixture of ethylene oxide, propylene oxide and
cyclohexene oxide.
30
The skilled person will also understand that substituted and unsubstituted
oxetanes can be used in place of, and in addition to, the epoxides of the second
aspect of the invention. Suitable oxetanes include unsubstituted or substituted
oxetanes (preferably substituted at the 3-position by halogen, alkyl
17
(unsubstituted or substituted by –OH or halogen), amino, hydroxyl, aryl (e.g.
phenyl), alkylaryl (e.g. benzyl)). Exemplary oxetanes include oxetane, 3-ethyl-3-
oxetanemethanol, oxetane-3-methanol, 3-methyl-3-oxetanemethanol, 3-
methyloxetane, 3-ethyloxetane, etc.
5
The term anhydride relates to any compound comprising an anhydride moiety in
a ring system (i.e. a cyclic anhydride). Preferably, the anhydrides which are
useful in the present invention have the following formula:
Wherein m’’ is 1, 2, 3, 4, 5, or 6 (preferably 1 or 2), each Ra1, Ra2, Ra3 and Ra4 10 is
independently selected from hydrogen, halogen, hydroxyl, nitro, alkoxy, aryloxy,
heteroaryloxy, amino, alkylamino, imine, nitrile, acetylide, carboxylate or
optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl,
heteroaryl, alkylaryl or alkylheteroaryl; or two or more of Ra1, Ra2, Ra3 and Ra4
15 can be taken together to form a saturated, partially saturated or unsaturated 3 to
12 membered, optionally substituted ring system, optionally containing one or
more heteroatoms, or can be taken together to form a double bond. Each Q is
independently C, O, N or S, preferably C, wherein Ra3 and Ra4 are either present,
or absent, and can either be or , according to the valency of
Q. It will be appreciated that when Q is C, and is , Ra3 and Ra4 20 (or
two Ra4 on adjacent carbon atoms) are absent. The skilled person will appreciate
that the anhydrides may be obtained from “green” or renewable resources.
Preferable anhydrides are set out below.
18
, , , , ,
, , , , ,
, , , , .
5 The term lactone relates to any cyclic compound comprising a–C(O)O- moiety in
the ring. Preferably, the lactones which are useful in the present invention have
the following formula:
Wherein m is 1 to 20 (e.g. 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17,
18, 19 or 20), preferably 2, 4, or 5; and RL1 and RL2 10 are independently selected
from hydrogen, halogen, hydroxyl, nitro, alkoxy, aryloxy, heteroaryloxy, amino,
alkylamino, imine, nitrile, acetylide, carboxylate or optionally substituted aliphatic,
heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl, alkylaryl or
alkylheteroaryl. Two or more of RL1 and RL2 can be taken together to form a
15 saturated, partially saturated or unsaturated 3 to 12 membered, optionally
substituted ring system, optionally containing one or more heteroatoms. When m
is 2 or more, the RL1 and RL2 on each carbon atom may be the same or different.
Preferably RL1 and RL2 are selected from hydrogen or alkyl. Preferably, the
lactone has the following structure:
20 , , . , , .
19
The term lactide is a cyclic compound containing two ester groups. Preferably,
the lactides which are useful in the present invention have the following formula:
5 Wherein m’ is 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, (preferably 1 or 2, more preferably, 1)
and RL3 and RL4 are independently selected from hydrogen, halogen, hydroxyl,
nitro, alkoxy, aryloxy, heteroaryloxy, amino, alkylamino, imine, nitrile, acetylide,
carboxylate or optionally substituted aliphatic, heteroaliphatic, alicyclic,
heteroalicyclic, aryl, heteroaryl, alkylaryl or alkylheteroaryl. Two or more of RL3
and RL4 10 can be taken together to form a saturated, partially saturated or
unsaturated 3 to 12 membered, optionally substituted ring system, optionally
containing one or more heteroatoms, When m’ is 2 or more, the RL3 and RL4 on
each carbon atom may be the same or different or one or more RL3 and RL4 on
adjacent carbon atoms can be absent, thereby forming a double or triple bond. It
15 will be appreciated that while the compound has two moieties represented by (-
CRL3R
L4)m’, both moieties will be identical. Preferably, m’ is 1, RL4 is H, and RL3 is
H, hydroxyl or a C1-6alkyl, preferably methyl. The stereochemistry of the moiety
represented by (-CRL3R
L4)m’ can either be the same (for example RR-lactide or
SS-lactide), or different (for example, meso-lactide). The lactide may be a
20 racemic mixture, or may be an optically pure isomer. Preferably, the lactide has
the following formula:
, or .
The term “lactone and/or lactide” used herein encompasses a lactone, a lactide
25 and a combination of a lactone and a lactide. Preferably, the term “lactone
and/or lactide” means a lactone or a lactide.
20
Preferred optional substituents of the groups Ra1, Ra2, Ra3, Ra4, RL1, RL2, RL3 and
R
L4 include halogen, nitro, hydroxyl, unsubstituted aliphatic, unsubstituted
heteroaliphatic unsubstituted aryl, unsubstituted heteroaryl, alkoxy, aryloxy,
5 heteroaryloxy, amino, alkylamino, imine, nitrile, acetylide, and carboxylate.
DETAILED DESCRIPTION
In the first aspect of the invention, there is provided a catalyst of formula (I):
10 (I)
wherein:
M1 and M2 are independently selected from Zn(II), Cr(II), Co(II), Cu(II), Mn(II),
Mg(II), Ni(II), Fe(II), Ti(II), V(II), Cr(III)-X, Co(III)-X, Mn(III)-X, Ni(III)-X, Fe(III)-X,
Ca(II), Ge(II), Al(III)-X, Ti(III)-X, V(III)-X, Ge(IV)-(X)2 or Ti(IV)-(X)2;
15 wherein at least one of M1 or M2 is selected from Ni(II) and Ni(III)-X;
R1 and R2 are independently selected from hydrogen, halide, a nitro group, a
nitrile group, an imine, an amine, an ether group, a silyl group, a silyl ether
group, a sulfoxide group, a sulfonyl group, a sulfinate group or an acetylide
group or an optionally substituted alkyl, alkenyl, alkynyl, haloalkyl, aryl,
20 heteroaryl, alkoxy, aryloxy, alkylthio, arylthio, alicyclic or heteroalicyclic group;
R3 is independently selected from optionally substituted alkylene, alkenylene,
alkynylene, heteroalkylene, heteroalkenylene, heteroalkynylene, arylene,
21
heteroarylene or cycloalkylene, wherein alkylene, alkenylene, alkynylene,
heteroalkylene, heteroalkenylene and heteroalkynylene, may optionally be
interrupted by aryl, heteroaryl, alicyclic or heteroalicyclic;
R5 is independently selected from H, or optionally substituted aliphatic,
5 heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl, alkylheteroaryl or
alkylaryl;
E1 is C, E2 is O, S or NH or E1 is N and E2 is O;
E3, E4, E5 and E6 are selected from N, NR4, O and S, wherein when E3, E4,
E5 or E6 are N, is , and wherein when E3, E4, E5 or E6 are NR4,
10 O or S, is ; R4 is independently selected from H, or optionally
substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl,
alkylheteroaryl or alkylaryl;
X is independently selected from OC(O)Rx, OSO2Rx, OSORx, OSO(Rx)2,
15 S(O)Rx, ORx, phosphinate, halide, nitrate, hydroxyl, carbonate, amino, amido or
optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl or
heteroaryl;
Rx is independently hydrogen, or optionally substituted aliphatic, haloaliphatic,
heteroaliphatic, alicyclic, heteroalicyclic, aryl, alkylaryl or heteroaryl; and
20 G is absent or independently selected from a neutral or anionic donor ligand
which is a Lewis base.
Each of the occurrences of the groups R1 and R2 may be the same or different.
Preferably R1 and R2 are independently selected from hydrogen, halide, amino,
25 nitro, sulfoxide, sulfonyl, sulfinate, silyl, silyl ether and an optionally substituted
alkyl, alkenyl, aryl, heteroaryl, alkoxy, aryloxy or alkylthio. Preferably R2 is the
same. Preferably, each occurrence of R2 is the same, and is hydrogen.
Even more preferably, R2 is hydrogen and R1 is independently selected from
30 hydrogen, halide, amino, nitro, sulfoxide, sulfonyl, sulfinate, silyl, silyl ether and
optionally substituted alkyl, alkenyl, aryl, heteroaryl, alkoxy, aryloxy, alkylthio,
arylthio, such as hydrogen, C1-6alkyl (e.g. haloalkyl), alkoxy, aryl, halide, nitro,
22
sulfonyl, silyl and alkylthio, for example, tBu, iPr, Me, OMe, H, nitro, SO2Me,
SiEt3, halogen or phenyl.
Each occurrence of R1 can be the same or different, and R1 and R2 can be the
5 same or different. Preferably each occurrence of R1 is the same. Preferably each
occurrence of R2 is the same. Preferably, each occurrence of R1
is the same,
and each occurrence of R2 is the same, and R1 is different to R2.
Preferably both occurrences of R1 are the same, and are selected from
10 hydrogen, halide, amino, nitro, sulfoxide, sulfonyl, sulfinate, silyl, silyl ether and
an optionally substituted alkyl, alkenyl, aryl, heteroaryl, alkoxy, aryloxy or
alkylthio. More preferably both occurrences of R1 are the same, and are selected
from halide, sulfoxide, silyl, and an optionally substituted alkyl, heteroaryl or
alkoxy. Still more preferably both occurrences of R1 are the same, and are
15 selected from tbutyl, methoxy, trialkylsilyl such as triethylsilyl, bromide,
methanesulfonyl, or piperidinyl. More preferably still both occurrences of R1 are
the same, and are selected from t-butyl or trialkylsilyl. Most preferably, both
occurrences of R1 are the same, and are tbutyl.
20 It will be appreciated that the group R3 can be a disubstituted alkyl, alkenyl,
alkynyl, heteroalkyl, heteroalkenyl or heteroalkynyl group which may optionally
be interrupted by an aryl, heteroaryl, alicyclic or heteroalicyclic group, or may be
a disubstituted aryl or cycloalkyl group which acts as a bridging group between
two nitrogen centres in the catalyst of formula (I). Thus, where R3 is an alkylene
25 group, such as dimethylpropylenyl, the R3 group has the structure –CH2-
C(CH3)2-CH2-. The definitions of the alkyl, aryl, cycloalkyl etc groups set out
above therefore also relate respectively to the divalent alkylene, arylene,
cycloalkylene etc groups set out for R3, and may be optionally substituted.
Exemplary options for R3 include ethylenyl, 2,2-fluoropropylenyl, 2,2-
30 dimethylpropylenyl, propylenyl, butylenyl, phenylenyl, cyclohexylenyl or
biphenylenyl. When R3 is cyclohexylenyl, it can be the racemic, RR- or SSforms.

23
R3 can be independently selected from substituted or unsubstituted alkylene and
substituted or unsubstituted arylene, preferably substituted or unsubstituted
propylenyl, such as propylenyl and 2,2-dimethylpropylenyl, and substituted or
unsubstituted phenylenyl or biphenylenyl. Preferably both occurrences of R3 are
5 the same. Even more preferably R3 is a substituted propylenyl, such as 2,2-
di(alkyl)propylenyl, especially 2,2-di(methyl)propylenyl.
R3 can be independently selected from substituted or unsubstituted alkylene,
alkenylene, alkynylene, heteroalkylene, heteroalkenylene or heteroalkynylene,
10 arylene or cycloalkylene. Preferably, R3 is selected from substituted or
unsubstituted alkylene, cycloalkylene, alkenylene, heteroalkylene and arylene.
More preferably, R3 is selected from 2,2-dimethylpropylenyl, -CH2 CH2 CH2-, -
CH2CH(CH3)CH2-, -CH2C(CH2C6H5)2CH2-, phenylene, -CH2 CH2-, -CH2 CH2 CH2
CH2-, -CH2 CH2N (CH3) CH2 CH2-, 1,4-cyclohexandiyl or -CH2CH2CH (C2H5)-.
Still more preferably R3 is selected from 2,2-dimethylpropylenyl, -CH2 CH2 CH2- 15 , -
CH2CH(CH3)CH2-, -CH2C(CH2C6H5)2CH2-, -CH2CH2CH (C2H5)-, -CH2 CH2 CH2
CH2-. More preferably still, R3 is selected from 2,2-dimethylpropylenyl, -
CH2C(CH2C6H5)2CH2-, CH2CH(CH3)CH2 and -CH2 C(C2H5)2 CH2-.
20 Most preferably R3 is a substituted propylenyl, such as 2,2-di(alkyl)propylenyl,
more preferably 2,2-dimethylpropylenyl.
Preferably each R4 is independently selected from hydrogen, and an optionally
substituted alkyl, alkenyl, alkynyl, aryl, heteroalkyl, heteroalkenyl, heteroalkynyl
25 or heteroaryl. Preferably R4 is hydrogen. Preferably each R4 is the same.
Preferably, each R4 is the same, and is selected from hydrogen, and an
optionally substituted alkyl, alkenyl, alkynyl, aryl, heteroalkyl, heteroalkenyl,
heteroalkynyl or heteroaryl. Exemplary options for R4 include H, Me, Et, Bn, iPr,
tBu or Ph. A further exemplary option is –CH2-(pyridine). Even more preferably,
30 each R4 is hydrogen.
Preferably each R5 is independently selected from hydrogen, and optionally
substituted aliphatic or aryl. More preferably, each R5 is independently selected
from hydrogen, and optionally substituted alkyl or aryl. Even more preferably,
24
each R5 is the same, and is selected from hydrogen, and optionally substituted
alkyl or aryl. Exemplary R5 groups include hydrogen, methyl, ethyl, phenyl and
trifluoromethyl, preferably hydrogen, methyl or trifluoromethyl. Even more
preferably, each R5 is hydrogen.
5
Preferably both occurrences of E1 are C and both occurrences of E2 are the
same, and selected from O, S or NH. Even more preferably, both occurrences of
E1 are C and both occurrences of E2 are O.
10 Preferably, each occurrence of E3, E4, E5 and E6 are NR4. Even more
preferably, E3, E4, E5 and E6 are the same and are NH. In other words, the
catalyst of the first aspect preferably has the following preferred structure:
(II)
Each X is independently selected from OC(O)Rx
, OSO2R
x
, OS(O)Rx
, OSO(Rx
)2,
S(O)Rx
, ORx
15 , phosphinate, halide, nitro, hydroxyl, carbonate, amino, nitrate,
amido and optionally substituted, aliphatic, heteroaliphatic (for example silyl),
alicyclic, heteroalicyclic, aryl or heteroaryl. Preferably each X is independently
OC(O)Rx
, OSO2R
x
, OS(O)Rx
, OSO(Rx
)2, S(O)Rx
, ORx
, halide, nitrate, hydroxyl,
carbonate, amino, nitro, amido, alkyl (e.g. branched alkyl), heteroalkyl, (for
20 example silyl), aryl or heteroaryl. Even more preferably, each X is independently
OC(O)Rx
, ORx
, halide, carbonate, amino, nitro, alkyl, aryl, heteroaryl,
phosphinate or OSO2R
x
. Preferred optional substituents for when X is aliphatic,
heteroaliphatic, alicyclic, heteroalicyclic, aryl or heteroaryl include halogen,
hydroxyl, nitro, cyano, amino, or substituted or unsubstituted aliphatic,
25 heteroaliphatic, alicyclic, heteroalicyclic, aryl or heteroaryl. Each X may be the
25
same or different and preferably each X is the same. It will also be appreciated
that X may form a bridge between the two metal centres.
R
x
is independently hydrogen, or optionally substituted aliphatic, haloaliphatic,
5 heteroaliphatic, alicyclic, heteroalicyclic, aryl, alkylaryl, or heteroaryl. Preferably,
R
x
is alkyl, alkenyl, alkynyl, heteroalkyl, aryl, heteroaryl, cycloalkyl, or alkylaryl.
Preferred optional substitutents for Rx
include halogen, hydroxyl, cyano, nitro,
amino, alkoxy, alkylthio, or substituted or unsubstituted aliphatic, heteroaliphatic,
alicyclic, heteroalicyclic, aryl or heteroaryl (e.g. optionally substituted alkyl, aryl,
10 or heteroaryl).
Exemplary options for X include OAc, OC(O)CF3, halogen, OSO(CH3)2, Et, Me,
OMe, OiPr, OtBu, Cl, Br, I, F, N(iPr)2 or N(SiMe3)2, OPh, OBn, salicylate, dioctyl
phosphinate, etc.
15
Preferably each X is the same, and is selected from OC(O)Rx
, ORx
, halide,
carbonate, amino, nitro, alkyl, aryl, heteroaryl, phosphinate or OSO2R
x
, R
x
is
alkyl, alkenyl, alkynyl, heteroalkyl, aryl, heteroaryl or alkylaryl. More preferably
each X is the same and is OC(O)Rx
, ORx
, halide, alkyl, aryl, heteroaryl,
phosphinate or OSO2R
x
20 . Still more preferably each X is the same and is
OC(O)Rx. More preferably still each X is the same and is selected from OAc,
O2CCF3, or O2C(CH2)3Cy. Most preferably each X is the same and is OAc.
Preferably each R
x
is the same and is selected from an optionally substituted
25 alkyl, alkenyl, alkynyl, heteroalkyl, aryl, heteroaryl, cycloalkyl or alkylaryl. More
preferably each Rx
is the same and is an optionally substituted alkyl, alkenyl,
heteroalkyl, aryl, heteroaryl, cycloalkyl or alkylaryl. Still more preferably each R
x
is the same and is an optionally substituted alkyl, alkenyl, heteroalkyl; or
cycloalkyl. More preferably still R
x
is an optionally substituted alkyl, heteroalkyl or
cycloalkyl. Most preferably R
x
30 is an optionally substituted alkyl.
As detailed above, M1 and M2 are independently selected from any of: Zn(II),
Cr(III)-X, Cr(II), Co(III)-X, Co(II), Cu(II), Mn(III)-X, Mn(II), Mg(II), Ni(II), Ni(III)-X,
26
Fe(II), Fe(III)-X, Ca(II), Ge(II), Ti(II), Al(III)-X, Ti(III)-X, V(II), V(III)-X, Ge(IV)-(X)2
or Ti(IV)-(X)2, wherein at least one of M1 and M2 is selected from Ni(II) and
Ni(III)-X, still more preferably however at least one of M1 and M2 is Ni(II).
5 Preferably, M1 and M2 are independently selected from Zn(II), Cr(III)-X, Co(II),
Cu(II), Mn(II), Mg(II), Ni(II), Ni(III)-X, Fe(II), Fe(III) and V(II), even more
preferably, M1 and M2 are independently selected from Zn(II), Cr(III)-X, Co(II),
Mn(II), Mg(II), Ni(II), Ni(III)-X, Fe(II), and Fe(III)-X, and even more preferably, M1
and M2 are independently selected from Zn(II), Mg(II), Ni(II) and Ni(III)-X,
10 wherein at least one of M1 and M2 is selected from Ni(II) and Ni(III)-X, still more
preferably at least one of M1 and M2 is Ni(II).
Most preferably, both M1 and M2 are selected from Ni(II) and Ni(III)-X, still most
preferably both M1 and M2 are Ni(II).
15
It will be appreciated that when one of M1 or M2 is Cr(III), Co(III), Mn(III), Ni(III),
Fe(III), Al(III), Ti(III) or V(III) the catalyst of formula (I) will contain an additional X
group co-ordinated to the metal centre, wherein X is as defined above. It will
also be appreciated that when one of M1 or M2 is Ge(IV) or Ti(IV), the catalyst of
20 formula (III) will contain two additional X group co-ordinated to the metal centre,
wherein X is as defined above. In certain embodiments, when one of M1 or M2 is
Ge(IV)-(X)2 or Ti(IV)-(X)2, both G may be absent.
When G is not absent, it is a group which is capable of donating a lone pair of
25 electrons (i.e. a Lewis base). In certain embodiments, G is a nitrogencontaining
Lewis base. Each G may be neutral or negatively charged. If G is
negatively charged, then one or more positive counterions will be required to
balance out the charge of the complex. Suitable positive counterions include
group 1 metal ions (Na+
, K+
, etc), group 2 metal ions (Mg2+, Ca2+, etc),
30 imidazolium ions, a positively charged optionally substituted heteroaryl,
heteroaliphatic or heteroalicyclic group, ammonium ions (i.e. N(R12)4
+
), iminium
ions (i.e. (R12)2C=N(R12)2
+
, such as bis(triphenylphosphine)iminium ions) or
phosphonium ions (P(R12)4
+
), wherein each R12 is independently selected from
hydrogen or optionally substituted aliphatic, heteroaliphatic, alicyclic,
27
heteroalicyclic, aryl or heteroaryl. Exemplary counterions include [H-B]+ wherein
B is selected from triethylamine, 1,8-diazabicyclo[5.4.0]undec-7-ene and 7-
methyl-1,5,7-triazabicyclo[4.4.0]dec-5-ene.
5 G is preferably independently selected from an optionally substituted
heteroaliphatic group, an optionally substituted heteroalicyclic group, an
optionally substituted heteroaryl group, a halide, hydroxide, hydride, a
carboxylate and water. More preferably, G is independently selected from water,
an alcohol (e.g. methanol), a substituted or unsubstituted heteroaryl (imidazole,
10 methyl imidazole (for example, N-methyl imidazole), pyridine, 4-
dimethylaminopyridine, pyrrole, pyrazole, etc), an ether (dimethyl ether,
diethylether, cyclic ethers, etc), a thioether, carbene, a phosphine, a phosphine
oxide, a substituted or unsubstituted heteroalicyclic (morpholine, piperidine,
tetrahydrofuran, tetrahydrothiophene, etc), an amine, an alkyl amine
15 trimethylamine, triethylamine, etc), acetonitrile, an ester (ethyl acetate, etc), an
acetamide (dimethylacetamide, etc), a sulfoxide (dimethylsulfoxide, etc), a
carboxylate, a hydroxide, hydride, a halide, a nitrate, a sulfonate, etc. In some
embodiments, one or both instances of G is independently selected from
optionally substituted heteroaryl, optionally substituted heteroaliphatic, optionally
20 substituted heteroalicyclic, halide, hydroxide, hydride, an ether, a thioether,
carbene, a phosphine, a phosphine oxide, an amine, an alkyl amine, acetonitrile,
an ester, an acetamide, a sulfoxide, a carboxylate, a nitrate or a sulfonate. In
certain embodiments, G may be a halide; hydroxide; hydride; water; a
heteroaryl, heteroalicyclic or carboxylate group which are optionally substituted
25 by alkyl, alkenyl, alkynyl, alkoxy, halogen, hydroxyl, nitro or nitrile. In preferred
embodiments, G is independently selected from halide; water; a heteroaryl
optionally substituted by alkyl (e.g. methyl, ethyl etc), alkenyl, alkynyl, alkoxy
(preferably methoxy), halogen, hydroxyl, nitro or nitrile. In some embodiments,
one or both instances of G is negatively charged (for example, halide). In further
30 embodiments, one or both instances of G is an optionally substituted heteroaryl.
Exemplary G groups include chloride, bromide, pyridine, methylimidazole (for
example N-methyl imidazole) and dimethylaminopyridine (for example, 4-
methylaminopyridine).
28
It will be appreciated that when a G group is present, the G group may be
associated with a single M metal centre as shown in formula (I), or the G group
may be associated with both metal centres and form a bridge between the two
metal centres, as shown below in formula (Ia):
5 (Ia)
Wherein R1, R2, R3, R4, R5, M1, M2, G, X, E1 and E2, are as defined for formula (I)
and formula (II).
It will also be appreciated that X may form a bridge between the two metal
10 centres.
The skilled person will understand that, in the solid state, the catalysts of the first
aspect may be associated with solvent molecules such as water, or alcohol (e.g.
methanol or ethanol). It will be appreciated that the solvent molecules may be
15 present in a ratio of less than 1:1 relative to the molecules of catalyst of the first
aspect (i.e. 0.2:1, 0.25:1, 0.5:1), in a ratio of 1:1, relative to the molecules of
catalyst of the first aspect, or in a ratio of greater than 1:1, relative to the
molecules of catalyst of the first aspect.
The skilled person will understand that, in the solid state, the catalysts of the first
20 aspect may form aggregates. For example, the catalyst of the first aspect may
be a dimer, a trimer, a tetramer, a pentamer, or higher aggregate.
It will be appreciated that the preferred features described above for the catalyst
of the first aspect may be present in combination mutatis mutandis.
29
For example, in preferred embodiments of the first aspect, each occurrence of
R2 and R5 are H, E1 is C and E2 is O, S or NH (preferably E2 is O) and, E3-E6
are NR4.
5 Preferably, each occurrence of R2 and R5 are H, R3 is an optionally substituted
or unsubstituted alkylene and substituted or unsubstituted arylene wherein
alkylene, may optionally be interrupted by aryl, heteroaryl, alicyclic or
heteroalicyclic, E1 is C and E2 is O, S or NH (preferably E2 is O), each
occurrence of E3 to E6 is NR4, R4 is hydrogen or alkyl (preferably hydrogen), each
X is independently OC(O)Rx
, ORx
10 , halide, carbonate, amino, nitro, alkyl, aryl,
heteroaryl, phosphinate or OSO2R
x
, R
x
is alkyl, alkenyl, alkynyl, heteroalkyl, aryl,
heteroaryl or alkylaryl, each R1 is independently hydrogen, alkyl, alkenyl, aryl,
heteroaryl, alkoxy, alkylthio, halide, amino, nitro, sulfoxide, sulfonyl, sulfinate,
silyl or silyl ether, each G (where present) is independently selected from halide;
15 water; a heteroaryl optionally substituted by alkyl (e.g. methyl, ethyl etc), alkenyl,
alkynyl, alkoxy (preferably methoxy), halogen, hydroxyl, nitro or nitrile, at least
one of M1 and M2 is Ni(II) or Ni(III)-X, and the remaining M1 or M2 is selected
from Mg(II), Zn(II), Cr(III)-X, Co(II), Co(III)-X, Mn(II), Ni(II), Ni(III)-X, Fe(II), and
Fe(III)-X.
20
Even more preferably, each occurrence of R2 and R5 are H, R3 is an optionally
substituted or unsubstituted alkylene and substituted or unsubstituted arylene, E1
is C and E2 is O, S or NH (preferably E2 is O), each occurrence of E3 to E6 is
NR4, R4 is hydrogen or alkyl (preferably hydrogen), each X is the same, and is
OC(O)Rx
, ORx
25 , halide, carbonate, amino, nitro, alkyl, aryl, heteroaryl,
phosphinate or OSO2R
x
, R
x
is alkyl, alkenyl, alkynyl, heteroalkyl, aryl, heteroaryl
or alkylaryl, each R1 is the same and is hydrogen, alkyl, alkenyl, aryl, heteroaryl,
alkoxy, alkylthio, halide, amino, nitro, sulfoxide, sulfonyl, sulfinate, silyl or silyl
ether and an optionally substituted alkyl, alkenyl, aryl, heteroaryl, alkoxy or
30 alkylthio, each G (where present) is independently selected from halide; water; a
heteroaryl optionally substituted by alkyl (e.g. methyl, ethyl etc), alkenyl, alkynyl,
alkoxy (preferably methoxy), halogen, hydroxyl, nitro or nitrile, at least one of M1
and M2 is Ni(II) or Ni(III)-X, and the remaining M1 or M2 is selected from Mg(II),
30
Zn(II), Cr(II), Cr(III)-X, Co(II), Co(III)-X, Mn(II), Ni(II), Ni(III)-X, Fe(II), and Fe(III)-
X, preferably both M1 and M2 are selected from Ni(II) and Ni(III)-X.
In a preferred embodiment, the catalyst of formula (I) has the formula (Ib):
5 (Ib)
Wherein:
Both occurrences of R1 are the same, and are selected from hydrogen, halide,
amino, nitro, sulfoxide, sulfonyl, sulfinate, silyl, silyl ether and an optionally
substituted alkyl, alkenyl, aryl, heteroaryl, alkoxy, aryloxy or alkylthio;
10 R3 is selected from substituted or unsubstituted alkylene, heteroalkylene arylene
or heteroarylene wherein alkylene and heteroalkylene may optionally be
interrupted by aryl, heteroaryl, alicyclic or heteroalicyclic;
Each X is the same, and is selected from OC(O)Rx
, ORx
, halide, carbonate,
amino, nitro, alkyl, aryl, heteroaryl, phosphinate or OSO2R
x
, R
x
is alkyl, alkenyl,
15 alkynyl, heteroalkyl, aryl, heteroaryl or alkylaryl;
R
x
is alkyl, alkenyl, alkynyl, heteroalkyl, aryl, heteroaryl or alkylaryl;
Each G (where present) is independently selected from halide; water; a
heteroaryl optionally substituted by alkyl, alkenyl, alkynyl, alkoxy, halogen,
hydroxyl, nitro or nitrile; and
20 at least one of M1 and M2 is Ni(II) or Ni(III)-X, and the remaining M1 or M2 is
selected from Mg(II), Zn(II), Cr(III)-X, Co(II), Co(III)-X, Mn(II), Ni(II), Ni(III)-X,
Fe(II), and Fe(III)-X.
31
Preferably R1 is hydrogen, halide, silyl, silyl ether, sulfonyl, and optionally
substituted alkyl, aryl or alkoxy.
Preferably, R3 is selected from propylenyl, 2,2-dimethylpropylenyl, and
5 substituted or unsubstituted phenylenyl or biphenylenyl. Even more preferably R3
is a substituted propylenyl, such as 2,2-di(alkyl)propylenyl.
Preferably, both M1 and M2 are selected from Ni(II) and Ni(III)-X. Even more
preferably, both M1 and M2 are Ni(II).
10
Preferably, X is OC(O)Rx
, ORx
, halide, alkyl, aryl, heteroaryl, phosphinate or
OSO2R
x
. Preferably, R
x
is alkyl, alkenyl, alkynyl, heteroalkyl, aryl, heteroaryl or
alkylaryl. Even more preferably, X is OC(O)Rx
, and Rx
is alkyl, alkenyl,
heteroalkyl, aryl, heteroaryl or alkylaryl, preferably Rx
is alkyl (e.g. methyl, ethyl,
15 propyl, t-butyl or trifluoromethyl).
G may be absent or present, and preferably G is absent.
In a more preferred embodiment, the catalyst of formula (I) has the formula (Ic):
20 (Ic)
wherein:
Both occurrences of R1 are the same, and are selected from halide, sulfoxide,
silyl, and an optionally substituted alkyl, heteroalicyclic or alkoxy;
32
R3 is selected from substituted or unsubstituted alkylenyl, cycloalkylenyl,
alkenylenyl, heteroalkylenyl and arylenyl wherein alkylenyl, alkenylenyl,
heteroalkylenyl, may optionally be interrupted by aryl, heteroaryl, alicyclic or
heteroalicyclic;
Each X is the same, and is OC(O)Rx
, R
x
5 is alkyl, alkenyl, heteroalkyl; or
cycloalkyl;
Each G is not present; and
Both M1 and M2 are selected from Ni(II) or Ni(III)-X.
10 In a still more preferred embodiment, the catalyst of formula (I) has the formula
(Id):
(Id)
Wherein:
15 Both occurrences of R1 are the same, and are selected from t-butyl, methoxy,
triethylsilyl, Br, SO2CH3, or piperidine;
R3 is selected from 2,2-dimethylpropylenyl, -CH2 CH2 CH2-, -CH2CH(CH3)CH2-, -
CH2C(CH2C6H5)2CH2-, phenylene, -CH2 CH2-, -CH2 CH2 CH2 CH2-, -CH2 CH2N
(CH3) CH2 CH2-, 1,4-cyclohexandiyl, -CH2CH2CH (C2H5) or CH2C(C2H5)2CH2-;
20 Each X is the same, and is selected from OAc, O2CCF3, or O2C(CH2)3Cy;
Each G is not present; and
Both M1 and M2 are selected from Ni(II) or Ni(III)-X.
33
In a still more preferred embodiment, the catalyst of formula (I) has the formula
(Ie):
(Ie)
Wherein:
5 Both occurrences of R1 are the same, and are selected from tBu or triethylsilyl;
R3 is selected from 2,2-dimethylpropylenyl, -CH2 CH2 CH2-, -CH2CH(CH3)CH2-, -
CH2C(CH2C6H5)2CH2-, -CH2 CH2 CH2 CH2-, CH2C(C2H5)2CH2 and -CH2CH2CH
(C2H5)-;
Each X is the same, and is selected from OAc, O2CCF3, or O2C(CH2)3Cy;
10 Each G is not present; and
Both M1 and M2 are selected from Ni(II) or Ni(III)-X.
In a still more preferred embodiment, the catalyst of formula (1) has the formula
(If):
34
(If)
Wherein:
Both occurrences of R1 are the same, and are tBu;
R3 is selected from 2,2-dimethylpropylenyl, -CH2C(CH2C6H5)2CH2- and -
5 CH2CH2CH(C2H5)-;
Each X is the same, and is OAc;
Each G is not present; and
Both M1 and M2 are selected from Ni(II) or Ni(III)-X.
10 The skilled person will appreciate that each of these preferred features can be
taken in combination, mutatis mutandis. For example, R1 is hydrogen, halide,
silyl, silyl ether, sulfonyl, and optionally substituted alkyl or alkoxy; R3 is selected
from propylenyl, 2,2-dimethylpropylenyl, and substituted or unsubstituted
phenylenyl or biphenylenyl; at least one of M1 and M2 is Ni(II) or Ni(III)-X, and the
15 remaining M1 or M2 is selected from Mg(II), Zn(II), Ni(II) and Ni(III)-X (preferably
both M1 and M2 are selected from Ni(II) and Ni(III)-X); X is OC(O)Rx
, ORx
, halide,
alkyl, aryl, heteroaryl, phosphinate or OSO2R
x
; R
x
is alkyl, alkenyl, alkynyl,
heteroalkyl, aryl, heteroaryl or alkylaryl; and G may be present or absent
(preferably G is absent).
20
Exemplary catalysts of the first aspect are as follows:
35
36
37
38
39
40
5 The catalysts of the first aspect are capable of polymerising (i) carbon dioxide
and an epoxide, (ii) an epoxide and an anhydride, and (iii) a lactide and/or a
lactone. Therefore, in a second aspect of the invention there is provided a
process for the reaction of carbon dioxide with an epoxide, an anhydride with an
epoxide, or a lactide and/or a lactone in the presence of a catalyst according to
10 the first aspect.
The process of the second aspect may be carried out in the presence of a chain
transfer agent. Suitable chain transfer agents include the chain transfer agents,
for example as defined by formula (II), in WO 2013/034750, the entire contents
15 of which are hereby incorporated by reference. For example, the chain transfer
agent may be water, or may comprise at least one amine (-NHR), alcohol (-OH),
carboxylic acid (CO2H) or thiol (-SH) moiety.
41
Examples of chain transfer agents useful in the second aspect include water,
mono-alcohols (i.e. alcohols with one OH group, for example, 4-
ethylbenzenesulfonic acid, methanol, ethanol, propanol, butanol, pentanol,
hexanol, phenol, cyclohexanol), diols (for example, 1,2-ethanediol, 1-2-
5 propanediol, 1,3-propanediol, 1,2-butanediol, 1-3-butanediol, 1,4-butanediol, 1,5-
pentanediol, 1,6-hexanediol, 1,2-diphenol, 1,3-diphenol, 1,4-diphenol, catechol
and cyclohexenediol), triols (glycerol, benzenetriol, 1,2,4-butanetriol,
tris(methylalcohol)propane, tris(methylalcohol)ethane,
tris(methylalcohol)nitropropane, trimethylolpropane, preferably glycerol or
10 benzenetriol), tetraols (for example, calix[4]arene, 2,2-bis(methylalcohol)-1,3-
propanediol, di(trimethylolpropane)), polyols (for example, dipentaerythritol, D-
(+)-glucose or D-sorbitol), dihydroxy terminated polyesters (for example
polylactic acid), dihydroxy terminated polyethers (for example poly(ethylene
glycol)), acids (such as diphenylphosphinic acid), starch, lignin, mono-amines
15 (i.e. methylamine, dimethylamine, ethylamine, diethylamine, propylamine,
dipropylamine, butylamine, dibutylamine, pentylamine, dipentylamine,
hexylamine, dihexylamine), diamines (for example1,4-butanediamine), triamines,
diamine terminated polyethers, diamine terminated polyesters, mono-carboxylic
acids (for example, 3,5-di-tert-butylbenzoic acid), dicarboxylic acids (for
20 example, maleic acid, malonic acid, succinic acid, glutaric acid or terephthalic
acid, preferably maleic acid, malonic acid, succinic acid, glutaric acid),
tricarboxylic acids (for example, citric acid, 1,3,5-benzenetricarboxylic acid or
1,3,5-cyclohexanetricarboxylic acid, preferably citric acid), mono-thiols, dithoils,
trithiols, and compounds having a mixture of hydroxyl, amine, carboxylic acid
25 and thiol groups, for example lactic acid, glycolic acid, 3-hydroxypropionic acid,
natural amino acids, unnatural amino acids, monosaccharides, disaccharides,
oligosaccharides and polysaccharides (including pyranose and furanose forms).
Preferably, the chain transfer agent is selected from cyclohexene diol, 1,2,4-
butanetriol, tris(methylalcohol)propane, tris(methylalcohol)nitropropane,
30 tris(methylalcohol)ethane, tri(methylalcohol)propane, tri(methylalcohol)butane,
pentaerythritol, poly(propylene glycol), glycerol, mono- and di- ethylene glycol,
propylene glycol, 2,2-bis(methylalcohol)-1,3-propanediol, 1,3,5-
benzenetricarboxylic acid, 1,3,5-cyclohexanetricarboxylic acid, 1,4-
42
butanediamine, 1,6-hexanediol, D-sorbitol, 1-butylamine, terephthalic acid, D-
(+)-glucose, 3,5-di-tert-butylbenzoic acid, and water.
The process of the second aspect may be carried out in the presence of a
5 solvent. Examples of solvents useful in the third aspect include toluene, diethyl
carbonate, dimethyl carbonate, dioxane, dichlorobenzene, methylene chloride,
propylene carbonate, ethylene carbonate, acetone, ethyl acetate,
tetrahydrofuran (THF), etc.
10 When the process of the second aspect involves the reaction of an epoxide, the
epoxide may be any compound comprising an epoxide moiety.
Preferably the epoxide is ethylene oxide, propylene oxide, butylene oxide or
cyclohexene oxide. More preferably the epoxide is propylene oxide.
15
In a preferred embodiment of the second aspect of the invention, there is
provided a process for the reaction of carbon dioxide with ethylene oxide,
butylene oxide, cyclohexane oxide or propylene oxide, more preferably
propylene oxide, an anhydride with ethylene oxide, butylene oxide, cyclohexene
20 oxide or propylene oxide, more preferably propylene oxide, or a lactide and/or a
lactone in the presence of a catalyst according to the first aspect.
Preferably, in the preferred embodiment of the second aspect, the catalyst of the
first aspect is any one of those listed above as exemplary.
25
The epoxide may be purified (for example by distillation, such as over calcium
hydride) prior to reaction with carbon dioxide or the anhydride. For example, the
epoxide may be distilled prior to being added to the reaction mixture comprising
the catalyst or catalyst system.
30
The process of the second aspect of the invention may be carried out at a
pressure of 1 to 100 atmospheres, preferably at 1 to 40 atmospheres, such as at
1 to 20 atmospheres, more preferably at 1 or 10 atmospheres. The catalysts
43
used in the process of the second aspect allow the reaction to be carried out at
low pressures.
The process of the second aspect of the invention may be carried out at a
5 temperature of about 0ºC to about 250ºC, preferably from about 40°C to about
160°C, even more preferably from about 50˚C to about 120˚C. The duration of
the process may be up to 168 hours, such as from about 1 minute to about 24
hours, for example from about 5 minutes to about 12 hours, e.g. from about 1 to
about 6 hours.
10
The process temperature, for copolymerisations of carbon dioxide and an
epoxide, may be used to control the product composition. When the temperature
of the process of the second aspect which involves reacting carbon dioxide and
an epoxide is increased, the selectivity of the catalyst towards the formation of
15 cyclic carbonate is also increased. The catalysts and processes may operate at
temperatures up to 250°C.
The process of the second aspect of the invention may be carried out at low
catalytic loading. For example, when the reaction involves copolymerisation of
20 carbon dioxide and an epoxide, the catalytic loading for the process is preferably
in the range of 1:1,000-100,000 catalyst:epoxide, more preferably in the region
of 1:1,000-300,000 catalyst:epoxide, even more preferably in the region of
1:10,000-100,000, and most preferably in the region of 1:50,000-100,000
catalyst:epoxide. When the process involves copolymerisation of an epoxide and
25 an anhydride, or the reaction of a lactide and/or lactone, the catalytic loading for
the process is preferably in the range of 1:1,000-300,000 catalyst: total monomer
content, more preferably in the region of 1:10,000-100,000 catalyst: total
monomer content, even more preferably in the region of 1:50,000-100,000
catalyst:total monomer content. The ratios above are molar ratios.
30
The catalysts of the first aspect, and in particular catalysts wherein both M1 and
M2 are selected from Ni(II) and Ni(III)-X, have high activity and selectivity for
producing polycarbonates by reacting carbon dioxide and an epoxide, optionally
44
in the presence of a chain transfer agent, and preferably at temperatures
between about 40°C to about 160°C. Thus, the reaction times for the process of
the second aspect can be less than 12 hours, and preferably from about 2 to
about 6 hours. In particular, catalysts of the invention have improved activity in
5 relation to di-substituted meso-epoxides (e.g. cyclohexene oxide) and monosubstituted
epoxides (e.g.propylene oxide), and furthermore improved selectivity
to mono-substituted epoxide reactants.
The process of the second aspect can be carried out in a batch reactor or a
continuous reactor.
10
It will be appreciated that the various features described above for the process of
the second aspect may be present in combination mutatis mutandis. All
preferred features of the first aspect apply equally to the second aspect and may
be present in combination mutatis mutandis.
15
The third aspect of the invention provides a product of the process of the second
aspect of the invention. All preferred features of the second aspect of the
invention apply to the third aspect of the invention mutatis mutandis.
20 When the process of the second aspect is carried out in the presence of a chain
transfer agent, it produces polymer chains which are terminated at substantially
all ends with hydroxyl groups (i.e. polycarbonate polyols or polyester polyols). By
“substantially”, it is meant that at least 90% of the resultant polymer chains,
preferably at least 95% of the resultant polymer chains, and even more
25 preferably at least 98%, and even more preferably at least about 99% of the
resultant polymer chains are terminated at all ends in hydroxyl groups. In order
for at least 90% of the resultant polymer chains to be terminated at all ends with
hydroxyl groups, it is preferred for the process of the second aspect to be carried
out in the presence of at least about 4 equivalents of chain transfer agent,
30 relative to the amount of catalyst. In order for at least 95% of the resultant
polymer chains to be terminated at all ends with hydroxyl groups, it is preferred
for the process of the second aspect to be carried out in the presence of at least
about 10 equivalents of chain transfer agent, relative to the amount of catalyst.
45
In order for at least 98% of the resultant polymer chains to be terminated at all
ends with hydroxyl groups, it is preferred for the process of the second aspect to
be carried out in the presence of at least about 20 equivalents of chain transfer
agent, relative to the amount of catalyst. Thus, polyols obtained by the process
5 of the second aspect are considered to form part of the third aspect of the
invention.
The chain transfer agent referred to in the second aspect may be used to control
the molecular weight (Mn) of the polymer products produced by the second
10 aspect. Preferably, the molecular weight (Mn) of the polymer products of the
third aspect is greater than about 200 g/mol. The molecular weight (Mn) of the
polymer products of the third aspect may be from about 200 g/mol to about
200,000 g/mol. The molecular weight of the polymers produced by the third
aspect can be measured by Gel Permeation Chromatography (GPC) using, for
15 example, a GPC-60 manufactured by Polymer Labs, using THF as the eluent at
a flow rate of 1 ml/min on Mixed B columns, manufactured by Polymer Labs.
Narrow molecular weight polystyrene standards can be used to calibrate the
instrument.
20 It is possible to produce polycarbonate polyols and polyester polyols having a Mn
of from about 200 g/mol to about 20,000 g/mol, preferably less than about
10,000 g/mol by adding a chain transfer agent to the process of the second
aspect.
25 It is also possible to produce polymers having a Mn of greater than about 20,000
g/mol from the process of the second aspect. Preferably, the polymer having a
Mn of greater than about 20,000 g/mol is a polycarbonate or a polyester, even
more preferably a polycarbonate. Preferably, the polymer having a Mn of greater
than about 20,000 g/mol is a polycarbonate and is produced carrying out the
30 process of the second aspect without adding a chain transfer agent (CTA).
The polymers produced by the second aspect may be produced to have a
polydispersity index (PDI) of less than about 2, more preferably less than about
1.5, and even more preferably less than about 1.2. Furthermore, it is possible to
46
control the molecular weight distribution so as to produce multi-modal or broad
molecular weight distribution polymers by addition of one or more chain transfer
agent(s).
5 The polymers produced by the process of the second aspect (e.g.
polycarbonates such as PCHC or PPC), are useful building blocks in the
preparation of various copolymeric materials. The polymers produced by the
process of the second aspect may undergo further reaction, for example to
produce polymeric products such as polyureas or polyamines. These processes
10 and reactions are well known to the skilled person (for example, refer to
WO2013/034750).
The polycarbonate or polyester polyols produced by the process of the second
aspect may be used in various applications and products which conventionally
use polyols, including (but not limited to) adhesives (such as hot melt adhesives
15 and structural adhesives), a binder (such as forest product binders, foundry core
binders and rubber crumb binders), coatings (such as powder coatings,
transport, e.g. automotive or marine coatings, fast cure coatings, self-healing
coatings, top coats and primers, varnishes, and coatings for marine applications,
e.g. oil rigs), elastomers (such as cast elastomers, fibres/spandex elastomers,
20 footwear elastomers, RIM/RRIM elastomers, synthetic leather elastomers,
technical microcellular elastomers and TPU elastomers), flexible foams (such as
viscoelastic foams), rigid foams (such as rigid and flexible panels, moulded rigid
foams, aerosol gap filling foam, spray foams, refrigeration foams, pour-in-place
foams, and foam slabs) and sealants (such as glazing sealants for commercial,
25 industrial and transport (e.g. automotive) applications, and construction
sealants). The polyamines and polyureas can be processed using methods
standard techniques known in the art, such as foaming.
It will be understood that the polycarbonate and polyester polyols produced by
30 the process of the second aspect may be mixed with other polyols prior to further
use or reaction.
47
The polycarbonates, and in particular, polycarbonates having a Mn of greater
than about 20,000 g/mol (e.g. produced without adding chain transfer agent to
the process of the second aspect) may have a number of beneficial properties
including high strength, high toughness, high gloss, high transparency, low haze,
5 high gas (e.g. oxygen and carbon dioxide) or water barrier properties, flame
resistance, UV resistance, high durability, rigidity and stiffness, compatability
with plasticizers, broad dimernsional stability temperature, biodegradability and
biocopatability, and modulus of elasticity and yield strength comparable to
LDPE. Thus, these polymers may be used in various applications and products,
10 such as electronic components, construction materials, data storage products,
automotive and aircraft products, security components, medical applications,
mobile phones, packaging (including bottles), optical applications (such as safety
glass, windscreens, etc).
15 Embodiments of the invention will now be described with reference to
accompanying examples and figures in which:-
Figure 1 shows the selectivity of various catalysts.
20 Figure 2 shows the activity of various catalysts.
Figure 3 is a close up from figure 2.
Examples
25 Example 1: Synthesis of nickel-containing catalysts
Ligands H2L
1-18 were synthesised by the method previously described by
Kember et al, Angew. Chem. Int. Ed., 2009, 48, 931-933.
48
Ligands H2L
1
, H2L
3, H2L
5
, H2L
6
, H2L
7
and H2L
8
(2 mmol) were dissolved in MeOH
(50 mL), Ni(OAc)2.4H2O (0.498 g, 4 mmol) was added portionwise over 15
5 minutes and the solution stirred overnight. The solvent was removed under
vacuum and excess water/AcOH was removed by azeotrope with toluene (3 x 40
mL) to give a green or blue solid.
[L1Ni2(OAc)2]: IR (ʋC=O, cm-1
, neat): 1581 and 1413. MALDI-TOF MS: m/z: 727.6
([M -OAc)]+
10 , 100%);
[L3Ni2(OAc)2]: IR (ʋC=O, cm-1
, neat): 1577 and 1413.
[L5Ni2(OAc)2]: IR (ʋC=O, cm-1
, neat): 1585 and 1413. APCI-MS: m/z: 829 ([M -2 -
OAc + -O2CH]+
, 100%);
[L6Ni2(OAc)2]: IR (ʋC=O, cm-1
, neat): 1577 and 1439. APCI-MS: m/z: 754 ([M -2 -
OAc + -O2CH]+
15 , 100%);
[L7Ni2(OAc)2]: IR (ʋC=O, cm-1
, neat): 1581 and 1413. APCI-MS: m/z: 757 ([M -2 -
OAc + -O2CH]+
, 100%).
[L8Ni2(OAc)2]: IR (ʋC=O, cm-1
, neat): 1581 and 1413. APCI-MS: m/z: 779.2 ([M -
-
OAc]+
, 75%), 765.2 ([M - 2 -OAc + -O2CH]+
, 95%).
20
49
Ligand H2L
x
(2 mmol) was dissolved in MeOH (50 mL), Ni(X)2.xH2O (4 mmol)
was added portionwise over 15 minutes and the solution stirred overnight. The
solvent was removed under vacuum and excess water/acid was removed by
5 azeotrope with toluene (3 x 40 mL) to give a green or blue solid.
[L1Ni2(O2CCF3)2]: IR (ʋC=O, cm-1
, neat): 1674 and 1480. ESI-MS: m/z = 779.3
(100%, [M - O2CCF3]
+
).
[L1Ni2(O2C(CH2)3Cy)2] ]: IR (ʋC=O, cm-1
, neat): 1581 and 1406: ESI-MS: m/z =
835.2 (100 %, [M - (O2C(CH2)3Cy)]+
10 ).
L
14Ni2(O2CCF3)2: IR (ʋC=O, cm-1
, neat): 1678 and 1480. ESI-MS: m/z: 711.2 ([M -2
-OAc + -O2CH]+
, 100%);
15
50
Ligand H2L
X
(2 mmol) was dissolved in MeOH (50 mL), Ni(OAc)2.4H2O (0.498 g,
4 mmol) was added portionwise over 15 minutes and the solution stirred
5 overnight. The solvent was removed under vacuum and excess water/acid was
removed by azeotrope with toluene (3 x 40 mL) to give a green or blue solid.
L
9Ni2(OAc)2: IR (ʋC=O, cm-1
, neat): 1573 and 1421. APCI-MS: m/z: 655.1 ([M -2 -
OAc + -O2CH]+
, 85%);
L
10Ni2(OAc)2: IR (ʋC=O, cm-1
, neat): 1577 and 1421. APCI-MS: m/z: 685.1 ([M -2 -
10
OAc + -O2CH]+
, 70%);
L
11Ni2(OAc)2: IR (ʋC=O, cm-1
, neat): 1581, 1413. APCI-MS: m/z: 1017.2 ([M -2 -
OAc + -O2CH]+
, 70%), 969.2 ([M -2 -OAc]+
, 100%);
L
12Ni2(OAc)2: IR (ʋC=O, cm-1
, neat): 1559 and 1417. APCI-MS: m/z: 725.1 ([M -2 -
OAc + -O2CH]+
15 , 50%);
L
13Ni2(OAc)2: IR (ʋC=O, cm-1
, neat): 1551 and 1436. APCI-MS: m/z: 629.1 ([M -2 -
OAc + -O2CH]+
, 50%);
51
L
14Ni2(OAc)2: IR (ʋC=O, cm-1
, neat): 1573 and 1410. APCI-MS: m/z: 725.2 ([M -
-
OAc]+
, 100%).
L
15Ni2(OAc)2: IR (ʋC=O, cm-1
, neat): 1566, 1413. APCI-MS: m/z: 685.1 ([M -2 -OAc
+ -O2CH]+
, 100%);
L
16Ni2(OAc)2: IR (ʋC=O, cm-1
, neat): 1577 and 1402. ESI-MS: m/z: 741.3 ([M -2 -
5
OAc + -O2CH]+
, 55 %); 755.3 ([M -
-OAc]+
, 20%).
L
17Ni2(OAc)2: IR (ʋC=O, cm-1
, neat): 1566, 1454. APCI-MS: m/z: 735.2 ([M -2 -OAc
+ -O2CH]+
, 100%);
L
18Ni2(OAc)2: IR (ʋC=O, cm-1
, neat): 1585, 1424. APCI-MS: m/z: 769.2 ([M - 2 -
OAc + -O2CH]+
10 , 95%);
Example 2: 1 atm copolymerisation of CHO with CO2 using Ni catalysts
The catalyst (0.0247 or 0.00494 mmol) was added to a dried Schlenk tube and
15 dried under vacuum for 30 minutes. CHO (2.5mL, 24.7 mmol) was added under
CO2 via a syringe, the vessel was heated to 100 °C and stirred for 2-16 hours,
after which the heating was removed and a sample taken for GPC/NMR
analysis.
20
Catalyst Time
(h)
TON TOF CHO
conversion
Selectivity
(CHO)
Mn (g/mol) PDI
[L1Ni2(OAc)2] 3 520 173.3 52 99.7 18000, 10400 1.02, 1.053
[L1Ni2(O2C(CH2)Cy)2] 4 467 116.8 46.7 100 14100, 7600 1.019, 1.055
[L1Ni2(O2CCF3)2] 3.25 562.5 173.1 56.25 100 18700 1.313
[L8Ni2(OAc)2] 4 102.5 25.63 10.25 90.4 3300 1.225
[L11Ni2(OAc)2] 4 441.5 110.4 44.15 100 15200, 7900 1.02, 1.086
[L9Ni2(OAc)2] 16 594 37.13 59.4 99.6 25400,
15900, 8100
1.004,
1.018, 1.019
52
[L15Ni2(OAc)2] 16 194.4 12.15 19.44 98.7 6200, 2800 1.034, 1.095
[L10Ni2(OAc)2] 5 356 71.2 35.6 99.8 4300 1.197
[L14Ni2(OAc)2] 3.5 562 160.6 56.2 99.7 20200, 8900 1.044, 1.107
[L18Ni2(OAc)2] 2.75 534 194.4 53.4 99.9 7300 1.25
Table 1: Copolymerisation of CHO and CO2 (1atm) using Ni catalysts
The catalysts show over 90% selectivity for polymer towards the reactant
cyclohexene oxide, >99% selectivity for polycarbonate over polyether (that is
5 >99% carbonate incorporation), high activities and activity under low pressures
(1 atm).
Example 3: Polymerisation of CO2 and PO at 90°C and 0.21 mmol [L1Ni2(OAc)2]
[L1Ni2(OAc)2] (0.21 mmol) was dissolved in propylene oxide (214 mmol) in a
10 Schlenk tube and the solution transferred into a pre-dried 100 mL stainless steel
Parr pressure vessel using a syringe. The vessel was charged with CO2 (3.0
MPa) and heated to 90 °C. The solution was stirred mechanically for 6 hours,
giving 7.5g of poly(propylene carbonate) (Mn 19000/9700, PDI 1.03/1.04) as a
white solid with a high selectivity for polymer and >99% carbonate linkages.
15
Example 4: Polymerisation of CO2 and PO at 80°C and 0.11 mmol [L1Ni2(OAc)2]
[L1Ni2(OAc)2] (0.11 mmol) was dissolved in propylene oxide (214 mmol) in a
Schlenk tube and the solution transferred into a pre-dried 100 mL stainless steel
Parr pressure vessel using a syringe. The vessel was charged with CO2 (4.0
20 MPa) and heated to 80 °C. The solution was stirred mechanically for 16 hours,
giving 7.4g of poly(propylene carbonate) (Mn 23000/11400, PDI 1.03/1.05) as a
white solid with a high selectivity for polymer and >99% carbonate linkages.
Example 5: Polymerisation of CO2 and PO at 90°C and 0.11 mmol of
[L1
25 Ni2(OAc)2]
[L1Ni2(OAc)2] (0.11 mmol) was dissolved in propylene oxide (214 mmol) in a
Schlenk tube and the solution transferred into a pre-dried 100 mL stainless steel
Parr pressure vessel using a syringe. The vessel was charged with CO2 (4.0
53
MPa) and heated to 90 °C. The solution was stirred mechanically for 17 hours,
giving 11.5g of poly(propylene carbonate) (Mn 39900/17600, PDI 1.03/1.09) as a
white solid with a high selectivity for polymer and >99% carbonate linkages.
5 Example 6: Polymerisation of CO2 and CHO at 100°C and 0.05 mmol of
[L1Ni2(OAc)2]
[L1Ni2(OAc)2] (0.05 mmol) was dissolved in cyclohexene oxide (50 mmol) in a
Schlenk. The vessel was degassed, charged with CO2 (0.1 MPa) and heated at
100 °C with magnetic stirring for 3 hours, giving 2.9g of poly(cyclohexene
10 carbonate). The polymer contained >99% carbonate linkages and was produced
with >99% selectivity (Mn 12000/5000, PDI 1.04/1.11).
Example 7: Polymerisation of CO2 and CHO at 80°C and 0.09 mmol of
[L1Ni2(OAc)2]
[L1
15 Ni2(OAc)2] (0.09 mmol) was dissolved in cyclohexene oxide (0.9 mmol) and
propylene oxide (0.9 mmol) and the solution transferred into a pre-dried 100 mL
stainless steel Parr pressure vessel using a syringe. The vessel was charged
with CO2 (1.5 MPa) and heated to 80 °C. The solution was stirred mechanically
for 7 hours, giving 13.1 g poly(cyclohexene-co-propylene) carbonate containing
20 >99 % carbonate linkages with a very high selectivity for polymer formation.
Example 8: Comparison of polymerisation of CO2 and PO with [L1Ni2(OAc)2],
[L5Ni2(OAc)2], and [L1Mg2(OAc)2] at a range of temperatures.
The catalyst ([L5Ni2(OAc)2] / [L1Ni2(OAc)2] / [L1Mg2(OAc)2]) (0.21 mmol) was
25 dissolved in propylene oxide (214 mmol) in a Schlenk tube and the solution
transferred into a pre-dried 100 mL stainless steel Parr pressure vessel using a
syringe. The vessel was charged with 0.4-0.5 MPa CO2 pressure and heated to
temperature. Once at temperature the CO2 pressure was topped up to 4.0 MPa.
The solution was stirred mechanically for the desired reaction time and the
30 reaction followed by in-situ ATR-FT-IR spectroscopy. The selectivity and activity
of the reaction was determined by ATR-FT-IR spectroscopy and confirmed with
1H NMR spectroscopy of the crude product. Results are set out in Figure 1 and
Figure 2.
54
Figure 1 shows that the selectivity of the catalyst having a Magnesium centre
[L1Mg2(OAc)2] is much lower than compared with a catalyst having the same
ligand structure but with a Nickel metal centre [L1Ni2(OAc)2]. Furthermore, figure
1 shows that the selectivity of catalysts having nickel metal centres remains high
5 over a broad temperature range, at 100C, the selectivity of the nickel centred
catalysts, [L1Ni2(OAc)2], [L5Ni2(OAc)2], is still at least 55%, whereas at 100C the
selectivity of the magnesium centred catalyst, [L1Mg2(OAc)2], has fallen to 0%.
Figure 2 shows that the activity of the catalyst having a Magnesium centre
[L1
10 Mg2(OAc)2] is much lower than compared with a catalyst having the same
ligand structure but with a Nickel metal centre [L1Ni2(OAc)2] across a
temperature range. Furthermore, figure 2 shows that the activity of the nickel
centred catalyst significantly increases at higher temperature, whilst retaining
selectivity for PPC, unlike the magnesium centred catalyst which shows less
15 activity and no selectivity at higher temperatures (see figure 1).
Figure 3 is a close up from figure 2 in the window 65-85 °C and shows more
closely the comparative activities of [L1Ni2(OAc)2] and [L1Mg2(OAc)2] in this
temperature range. It demonstrates more clearly that [L1Ni2(OAc)2] is surprisingly
20 twice as active as it’s magnesium analogue.
Example 9: Comparison of 1atm copolymerisation of CHO and CO2 with
equivalent Ni and Mg complexes under identical conditions
25
30
55
Cat. Cat
Loading
Time
(h)
TON TOF Selectivity
(CHO)
[L1Mg2(OAc)2] 1:1000 5 491 98 99.8
[L1Ni2(OAc)2] 1:1000 3 520 173.3 99.7
[L1Mg2(OAc)2] 1:5000 3 664 221 100
[L1Ni2(OAc)2] 1:5000 3.25 997 325.7 100
[L14Mg2(OAc)2] 1:1000 5 260 52 98.4
[L14Ni2(OAc)2] 1:1000 3.5 562 160.6 99.7
[L11Mg2(OAc)2] 1:1000 5 217.5 43.5 99.4
[L11Ni2(OAc)2] 1:1000 4 441.5 110.4 100
Table 2: Comparison of catalytic activity of equivalent Ni and Mg complexes
under identical conditions for CHO and CO2 (1 atm) copolymerisation.
5
The catalysts having nickel metal centres show over 99% selectivity to the
reactant cyclohexene oxide. The catalysts having nickel metal centres also
display a higher turnover number and a higher turnover frequency when
compared to catalysts having the same ligand structure but with magnesium
10 metal centres and when tested under identical reaction conditions. In particular,
the turnover frequency of the catalysts having nickel metal centres is in some
cases double that shown with catalysts having magnesium metal centres.
All of the features disclosed in this specification (including any accompanying
claims, abstract and drawings), and/or all of the steps of any method or process
15 so disclosed, may be combined in any combination, except combinations where
at least some of such features and/or steps are mutually exclusive.
Each feature disclosed in this specification (including any accompanying claims,
abstract and drawings) may be replaced by alternative features serving the
same, equivalent or similar purpose, unless expressly stated otherwise. Thus,
56
unless expressly stated otherwise, each feature disclosed is one example only of
a generic series of equivalent or similar features.
The invention is not restricted to the details of the foregoing embodiment(s). The
invention extends to any novel one, or any novel combination, of the features
5 disclosed in this specification (including any accompanying claims, abstract and
drawings), or to any novel one, or any novel combination, of the steps of any
method or process so disclosed.
10
15
20
25
57
WE CLAIM:
1. A catalyst of formula (I):
(I)
wherein:
5 M1 and M2 are independently selected from Zn(II), Cr(II), Co(II), Cu(II), Mn(II),
Mg(II), Ni(II), Fe(II), Ti(II), V(II), Cr(III)-X, Co(III)-X, Mn(III)-X, Ni(III)-X, Fe(III)-X,
Ca(II), Ge(II), Al(III)-X, Ti(III)-X, V(III)-X, Ge(IV)-(X)2 or Ti(IV)-(X)2;
wherein at least one of M1 or M2 is selected from Ni(II) and Ni(III)-X;
R1 and R2 are independently selected from hydrogen, halide, a nitro group, a
10 nitrile group, an imine, an amine, an ether group, a silyl group, a silyl ether
group, a sulfoxide group, a sulfonyl group, a sulfinate group or an acetylide
group or an optionally substituted alkyl, alkenyl, alkynyl, haloalkyl, aryl,
heteroaryl, alkoxy, aryloxy, alkylthio, arylthio, alicyclic or heteroalicyclic group;
R3 is independently selected from optionally substituted alkylene, alkenylene,
15 alkynylene, heteroalkylene, heteroalkenylene, heteroalkynylene, arylene,
heteroarylene or cycloalkylene, wherein alkylene, alkenylene, alkynylene,
heteroalkylene, heteroalkenylene and heteroalkynylene, may optionally be
interrupted by aryl, heteroaryl, alicyclic or heteroalicyclic;
20
R5 is independently selected from H, or optionally substituted aliphatic,
heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl, alkylheteroaryl or
alkylaryl;
58
E1 is C, E2 is O, S or NH or E1 is N and E2 is O;
E3, E4, E5 and E6 are selected from N, NR4, O and S, wherein when E3, E4, E5
or E6 are N, is , and wherein when E3, E4, E5 or E6 are NR4, O or
S, is ; R4 is independently selected from hydrogen, or optionally
5 substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl, heteroaryl,
alkylheteroaryl or alkylaryl;
X is independently selected from OC(O)Rx
, OSO2R
x
, OSORx
, OSO(Rx
)2, S(O)Rx
,
ORx
10 , phosphinate, halide, nitrate, hydroxyl, carbonate, amino, nitro, amido or
optionally substituted aliphatic, heteroaliphatic, alicyclic, heteroalicyclic, aryl or
heteroaryl;
Rx is independently hydrogen, or optionally substituted aliphatic, haloaliphatic,
heteroaliphatic, alicyclic, heteroalicyclic, aryl, alkylaryl or heteroaryl; and
15 G is absent or independently selected from a neutral or anionic donor ligand
which is a Lewis base.
2. The catalyst of claim 1, wherein at least one of M1 or M2 is Ni(II).
20 3. The catalyst of any preceding claim wherein one of M1 or M2 is selected from
Ni(II) and Ni(III)-X and the remaining occurrence of M1 and M2 is selected
from Zn(II), Cr(III)-X, Cr(II), Co(III)-X, Co(II), Cu(II), Mn(III)-X, Mn(II), Mg(II),
Ni(II), Ni(III)-X, Fe(II), Fe(III)-X, Ti(II), Ti(III)-X, V(II), V(III)-X, Ge(IV)-(X)2 and
Ti(IV)-(X)2.
25
4. The catalyst of claim 3, wherein the remaining occurrence of M1 and M2 is
selected from Zn(II), Cr(III)-X, Co(II), Cu(II), Mn(II), Mg(II), Ni(II), Ni(III)-X,
Fe(II), Fe(III)-X and V(II).
30
5. The catalyst of any of claims 3 or 4, wherein the remaining occurrence of M1
and M2 is selected from Zn(II), Cr(III)-X, Co(II), Mn(II), Mg(II), Ni(II), Ni(III)-X,
Fe(II), and Fe(III)-X.
59
6. The catalyst of any of claims 3-5 wherein the remaining occurrence of M1
and M2 is selected from any of: Zn(II), Mg(II), Ni(II), Co(II), Co(III)-X and
Ni(III)-X.
5
7. The catalyst of any preceding claim, wherein both M1 and M2 are Ni(II).
8. The catalyst of any preceding claim, wherein R3 is selected from substituted
10 or unsubstituted alkylene and substituted or unsubstituted arylene, preferably
substituted or unsubstituted phenylenyl or biphenylenyl and substituted or
unsubstituted propylenyl, such as propylene or 2,2-dimethylpropylenyl.
9. The catalyst of any preceding claim, wherein R3 is selected from substituted
15 or unsubstituted alkylene, alkenylene, alkynylene, heteroalkylene,
heteroalkenylene, heteroalkynylene, arylene, and cycloalkylene, preferably
R3 is selected from substituted or unsubstituted alkylene, cycloalkylene,
heteroalkylene, and arylene.
20
10. The catalyst of any preceding claim, wherein R3 is selected from 2,2-
dimethylpropylenyl, -CH2 CH2 CH2-, -CH2CH(CH3)CH2-, -
CH2C(CH2C6H5)2CH2-, phenylene, -CH2 CH2-, -CH2 CH2 CH2 CH2-, -CH2
CH2N (CH3) CH2 CH2-, 1,4-cyclohexandiyl, -CH2CH2CH (C2H5)- or -
25 CH2C(C2H5)2CH2-..
11. The catalyst of any preceding claim, wherein R3 is selected from is selected
from 2,2-dimethylpropylenyl, -CH2 CH2 CH2-
, -CH2CH(CH3)CH2-, -
CH2C(CH2C6H5)2CH2-, -CH2CH2CH (C2H5)-, -CH2 CH2 CH2 CH2-.
30
12. The catalyst of any preceding claim, wherein R3 is selected from a 2,2-
dimethylpropylenyl, -CH2C(CH2C6H5)2CH2-, -CH2C(C2H5)2CH2- and -
CH2CH2CH (C2H5)-.
60
13. The catalyst of any of claims 1 to 9, wherein R3 is a 2,2-dialkylpropylenyl, for
example 2,2-dimethylpropylenyl.
5 14. The catalyst of any preceding claim wherein both occurrences of R3 are the
same.
15. The catalyst of any preceding claim wherein E1 is C and E2 is O, S or NH,
10 preferably E2 is O.
16. The catalyst of any preceding claim, wherein E3, E4, E5 and E6 are NR4
17. The catalyst of any preceding claim, wherein R4 is selected from hydrogen or
an optionally substituted alkyl, alkenyl, alkynyl, heteroalkyl, heteroalkenyl,
15 heteroalkynyl, aryl or heteroaryl, such as hydrogen, methyl, ethyl, benzyl,
isopropyl, t-butyl, phenyl, or –CH2-pyridine, preferably R4 is hydrogen.
18. The catalyst of any preceding claim, wherein each occurrence of R4 is the
same.
20
19. The catalyst of any preceding claim wherein E3, E4, E5 and E6 are the
same, and are preferably NH.
20. The catalyst of any preceding claim wherein R1 is selected from hydrogen,
halide, amino, nitro, sulfoxide, sulfonyl, sulfinate, silyl, silyl ether, and
25 optionally substituted alkyl, alkenyl, aryl, heteroaryl, alkoxy, aryloxy, arylthio
or alkylthio, such as hydrogen, C1-6alkyl (e.g. haloalkyl), alkoxy, aryl, halide,
nitro, sulfonyl, silyl and alkylthio, for example, hydrogen, t-butyl, isopropyl,
methyl, methoxy, nitro, SO2CH3, triethylsilyl, halogen or phenyl.
30 21. The catalyst of any of claims 1-19, wherein R1 is selected from halide,
sulfoxide, silyl, and an optionally substituted alkyl, heteroaryl or alkoxy.
61
22. The catalyst of any of claims 1-19, wherein R1 is selected from t-butyl,
methoxy, triethylsilyl, bromide, SO2CH3, or piperidinyl.
23. The catalyst of claim 22, wherein R1 is selected from t-butyl or triethylsilyl.
24. The catalyst of any preceding claim, wherein both occurrences of R1 are the
5 same.
25. The catalyst of any preceding claim wherein X is selected from OC(O)Rx
,
OSO2R
x
, OS(O)Rx
, OSO(Rx
)2, S(O)Rx
, ORx
, phosphinate, halide, nitrate,
hydroxyl, carbonate, amino, nitro, amido, and optionally substituted alkyl,
heteroalkyl, (for example silyl), alicyclic, heteroalicyclic, aryl or heteroaryl,
preferably OC(O)Rx
, OSO2R
x
, OS(O)Rx
, OSO(Rx
)2, S(O)Rx
, ORx
10 , halide,
nitrate, hydroxyl, carbonate, amino, nitro, amido, alkyl (e.g. branched alkyl),
heteroalkyl, (for example silyl), aryl or heteroaryl, more preferably OC(O)Rx
,
ORx
, halide, carbonate, amino, nitro, alkyl, aryl, heteroaryl, phosphinate or
OSO2R
x
.
26. The catalyst of any preceding claim wherein X is selected from OC(O)Rx
15 ,
ORx
, halide, carbonate, amino, nitro, alkyl, aryl, heteroaryl, phosphinate or
OSO2R
x
.
27. The catalyst of any preceding claim wherein X is selected from OC(O)Rx
,
ORx
, halide, alkyl, aryl, heteroaryl, phosphinate or OSO2R
x
28. The catalyst of any preceding claim wherein X is OC(O)Rx
20
29. The catalyst of any preceding claim wherein X is selected from OAc,
O2CCF3, or O2C(CH2)3Cy.
30. The catalyst of any preceding claim wherein both occurrences of X are the
same.
31. The catalyst of any preceding claim wherein Rx
25 is an optionally substituted
alkyl, alkenyl, alkynyl, heteroalkyl, aryl, heteroaryl, cycloalkyl or alkylaryl.
62
32. The catalyst of any preceding claim wherein R
x
is selected from hydrogen, or
an optionally substituted aliphatic, haloaliphatic, heteroaliphatic, alicyclic,
heteroalicyclic, , aryl, alkylaryl or heteroaryl, preferably an optionally
substituted alkyl, alkenyl, heteroalkyl, aryl, heteroaryl, cycloalkyl or alkylaryl.
33. The catalyst of any preceding claim wherein R
x
5 is selected from an optionally
substituted alkyl, alkenyl, heteroalkyl, or cycloalkyl.
34. The catalyst of any preceding claim wherein R
x
is selected from an optionally
substituted alkyl, heteroalkyl, or cycloalkyl.
35. The catalyst of any preceding claim wherein R
x
is an optionally substituted
10 alkyl.
36. The catalyst of any preceding claim wherein both occurrences of Rx
are the
same.
37. The catalyst of any preceding claim wherein each occurrence of R2 and R5 is
hydrogen.
15 38. The catalyst of claim 1, wherein both occurrences of R1 are the same, and
are selected from hydrogen, halide, amino, nitro, sulfoxide, sulfonyl,
sulfinate, silyl, silyl ether and an optionally substituted alkyl, alkenyl, aryl,
heteroaryl, alkoxy, aryloxy or alkylthio; R2 is hydrogen; both occurrences of
R3 are the same, and are selected from substituted or unsubstituted alkylene
20 and substituted or unsubstituted arylene; E1 is C and E2 is O; E3, E4, E5 and
E6 are NR4; R4 is hydrogen; each X is the same, and is selected from
OC(O)Rx
, ORx
, halide, carbonate, amino, nitro, alkyl, aryl, heteroaryl,
phosphinate or OSO2R
x
, each R
x
is the same and is selected from alkyl,
alkenyl, alkynyl, heteroalkyl, aryl, heteroaryl or alkylaryl; each G (where
25 present) is the same and is selected from halide; water; a heteroaryl
optionally substituted by alkyl, alkenyl, alkynyl, alkoxy, halogen, hydroxyl,
nitro or nitrile; and one of M1 and M2 is Ni(II) or Ni(III)-X, and the remaining
M1 or M2 is selected from Mg(II), Zn(II), Cr(III)-X, Co(II), Co(III)-X Mn(II),
Ni(II), Ni(III)-X, Fe(II), and Fe(III)-X, preferably the remaining M1 or M2 is
30 selected from Mg(II), Zn(II), Ni(II) and Ni(III)-X.
63
39. The catalyst of claim 38, wherein both occurrences of M1 and M2 are
selected from Ni(II) and Ni(III)-X.
40. The catalyst of claim 38 or 39, wherein R1 is hydrogen, halide, silyl, silyl
ether, sulfonyl or optionally substituted alkyl or alkoxyl, preferably wherein G
5 is absent.
41. The catalyst of claim 1, of the formula (Ib):
(Ib)
wherein:
both occurrences of R1 are the same, and are selected from hydrogen, halide,
10 amino, nitro, sulfoxide, sulfonyl, sulfinate, silyl, silyl ether and an optionally
substituted alkyl, alkenyl, aryl, heteroaryl, alkoxy, aryloxy or alkylthio;
R3 is selected from substituted or unsubstituted alkylene, alkenylene, alkynylene,
heteroalkylene, heteroalkenylene or heteroalkynylene, cycloalkylene or arylene;
each X is the same, and is selected from OC(O)Rx
, ORx
, halide, carbonate,
amino, nitro, alkyl, aryl, heteroaryl, phosphinate or OSO2R
x
, R
x
15 is alkyl, alkenyl,
alkynyl, heteroalkyl, aryl, heteroaryl or alkylaryl;
R
x
is alkyl, alkenyl, alkynyl, heteroalkyl, aryl, heteroaryl or alkylaryl;
each G (where present) is independently selected from halide; water; a
heteroaryl optionally substituted by alkyl, alkenyl, alkynyl, alkoxy, halogen,
20 hydroxyl, nitro or nitrile; and
64
one occurrence of M1 and M2 is Ni(II) or Ni(III)-X, and the remaining occurrence
of M1 or M2 is selected from Mg(II), Zn(II), Cr(III)-X, Co(II), Co(III)-X, Mn(II), Ni(II),
Ni(III)-X, Fe(II), and Fe(III)-X.
5 42. The catalyst of claim 41, wherein R1 is hydrogen, halide, silyl, silyl ether,
sulfonyl, and optionally substituted alkyl or alkoxy.
43. The catalyst of claims 41 or 42, wherein R3 is selected from propylenyl, 2,2-
dimethylpropylenyl, and substituted or unsubstituted phenylenyl or
10 biphenylenyl, preferably R3 is a substituted propylenyl, such as 2,2-
di(alkyl)propylenyl.
44. The catalyst of any of claims 41-43, wherein M1 and M2 are selected from
Ni(II) and Ni(III)-X, preferably both M1 and M2 are Ni(II)
15
45. The catalyst of any of claims 41-44, wherein X is OC(O)Rx
, ORx
, halide, alkyl,
aryl, heteroaryl, phosphinate or OSO2R
x
, preferably OC(O)Rx
46. The catalyst of any of claims 41-45, wherein Rx
is alkyl, alkenyl, alkynyl,
20 heteroalkyl, aryl, heteroaryl or alkylaryl, preferably alkyl.
47. The catalyst of any of claims 41-46, wherein G is absent.
48. The catalyst of claim 1 of the formula:
65
66
67
68
69
70
49. A process for the reaction of:
5 a. carbon dioxide with an epoxide;
b. an epoxide and an anhydride; and/or
c. a lactide and/or a lactone,
in the presence of a catalyst as claimed in any one of claims 1 to 48, optionally
wherein the process is carried out in the presence of a chain transfer agent.
10 50. The process of claim 49 wherein the epoxide is ethylene oxide, butylene
oxide, propylene oxide or cyclohexene oxide, preferably propylene oxide.
51. The process according to claim 50 wherein the catalyst is any one of those
defined in claim 48.
71
52. The process of any of claims 49-51, wherein the process is carried out in a
continuous flow reactor, or a batch reactor.
53. The process of any of claims 49-52, wherein the reaction is carried out in a
continuous flow reactor.
5
54. A product of the process of any of claims 49 to 53.
55. A catalyst, product or process substantially as hereinbefore defined with
10 reference to one or more of the examples.
Dated this 12th day of January, 2017
MOHAN DEWAN
of R.K. DEWAN & COMPANY
15 APPLICANTS’ PATENT ATTORNEY
TO,
THE CONTROLLER OF PATENTS,
20 THE PATENT OFFICE
AT MUMBAI
ABSTRACT
CATALYSTS
The present invention relates to the field of polymerisation catalysts, and
systems comprising these catalysts for polymerising carbon dioxide and an
5 epoxide, a lactide and/or lactone, and/or an epoxide and an anhydride. The
catalyst is of formula (I):
(I)
wherein at least one of M1 or M2 is selected from Ni(II) and Ni(III)-X. A process
for the reaction of carbon dioxide with an epoxide; an epoxide and an anhydride;
10 and/or a lactide and/or a lactone in the presence of the catalyst is also
described.