WO 20101095575
1
PCT/FR2011/052990
PROCESS FOR PRODUCING NITRILE-FATTY ACID COMPOUNDS
The work which led to this invention received financial support from the
European Union in the context of Framework Program 7 (FP7/2007-2013) under
5 project No. 241718 EUROBIOREF.
The invention relates to a process for synthesizing a nitrile-fatty acid, also
referred to as heminitrile hereinafter, from unsaturated fatty acids, in the form of an
acid or a simple ester or a "complex" ester of triglyceride type, which is first of all
converted into an unsaturated fatty nitrile which is subjected to oxidative cleavage
10 using H202as oxidizing agent.
The nitrile-fatty acids of general formula NC-(CH2)n-COOH or of formula
NC(CH2)n(CH=CH)mCOOH (empirical formula Cn+2m+2H2n+2m+1N02) in the case
where the cleavage is carried out on a polyunsaturated acid, subsequently
referred to as diacid heminitriles or more simply heminitriles, are intermediate
15 compounds which can be used in the synthesis of an entire range of "fatty"
compounds such as w-amino acids, a-w-dinitriles, a-w-diamines or a-w-diacids.
The term "nitrile-fatty acid" is intended to mean linear nitrile-acid compounds
having from 6 to 15 carbon atoms.
Current developments in environmental matters are leading, in the fields of
20 energy and chemistry, to the exploitation of natural raw materials originating from
a renewable source being favored. This is the reason why some studies have
been undertaken to develop, on the industrial scale, processes using fatty
acids/esters (vegetable oils or animal fats) as raw material for the manufacture of
these fatty compounds, which can for example be used as polymerization
25 monomers for obtaining a polyamide.
There is an abundant literature on the synthesis of various difunctional a-w
compounds from unsaturated natural fatty acids. This literature is particularly
focused on "natural" oleic acid for the manufacture of w-amino acids, such as 9aminononanoic
acid, which is the precursor for the synthesis of Nylon 9. It should
30 in fact be recalled that the polyamide industry uses an entire range of monomers
consisting of long-chain w-amino acids, usually called Nylon, characterized by the
length of the methylene chain (-CH2)n separating two amide -CO-NH- functions.
WO 2010/095575
2
PCT/FR2011/052990
Thus it is that Nylon 6 (based on 6-aminohexanoic acid), Nylon 7, Nylon 8,
Nylon 9, Nylon 11, Nylon 13, and the like, are known.
The main studies have related to the synthesis of 9-aminononanoic acid,
which is the precursor of Nylon 9, from oleic acid of natural origin.
5 With regard to this particular monomer, mention may be made of the book
"n-Nylons, Their Synthesis, Structure and Properties" - 1997 publisher J. Wiley
and Sons, chapter 2.9 (pages 381 to 389) of which is devoted to Nylon 9 (or 9Nylon).
This article synthesizes the productions and studies carried out on the
subject. Mentioned therein (page 384) is a process developed in Japan using oleic
10 acid from soybean oil as raw material and consisting in carrying out an ozonolysis
of the oleic acid, followed by reductive ammoniation, thus resulting in 9aminononanoic
acid.
To complete the prior art which comes from the scientific literature, it is
necessary to mention the numerous articles published by E. H. Pryde and various
15 coauthors between 1962 and 1975 in - Journal of the American Oil Chemists
Society - "Amines from Aldehydic derived from the Ozonization of Soybean
Esters" vol. 42, pages 824-827, which makes reference (page 824) to prior studies
carried out by H. Otsuki and H. Funahashi relating to the ozonolysis of fatty acids
and "Nylon-9 from Unsaturated Fatty Derivatives: Preparation and
20 Characterization", vol. 52, pages 473-477, in which a comparison is made
between various routes of synthesis of 9-aminononanoic acid (pages 474 and
475), one of which is the nitrile route, with formation of the oleonitrile, which is
subsequently subjected to oxidative ozonolysis.
With regard to the patent literature, mention may be made of patent
25 GB 741 739 which describes the synthesis of 9-aminononanoic acid from
unsaturated fatty acids of formula R-CH=CH-(CH2h-COOH with a first
ammoniation step resulting in the corresponding nitrile, which is subjected in a
second step to oxidative ozonolysis resulting in the heminitrile of azelaic acid,
which is converted in a third step by hydrogenation to 9-aminononanoic acid.
30 The applicant has recently filed a patent application published under No.
FR 2 938 533 describing a process for synthesizing w-amino fatty acids from fatty
acids/esters of formula R1-CH=CH-(CH2)p-COOR2 in which R1 is H or a
WO 20101095575 PCT/FR2011/052990
3
hydrocarbon-based radical comprising from 4 to 11 carbon atoms and, where
appropriate, a hydroxyl function, R2 is H or an alkyl radical comprising from 1 to 4
carbon atoms and p is a whole index between 2 and 11. This process comprises
two variants which both pass through the formation of an intermediate w-
5 unsaturated nitrile, one of the variants comprising an ammoniation step and a step
of oxidative ozonolysis (of the w-unsaturated nitrile).
Moreover, a certain number of documents published since 1990 relate to
the synthesis of diacids (or diesters) from unsaturated fatty acids (or esters).
Patent application WO 93/12064 describes a process for synthesizing fatty
10 diacids (or esters) from unsaturated fatty acids (or esters). This process uses
aqueous hydrogen peroxide as oxidizing agent for the oxidative cleavage of the
double bond. It is carried out in one step and in the presence of a phase-transfer
agent.
European patent EP 0 666 838 describes a process for synthesizing fatty
15 diacids (or esters) from unsaturated fatty acids (or esters). This process is carried
out in two steps. The first step uses aqueous hydrogen peroxide to oxidize the
double bond while forming a vicinal diol. The second step uses oxygen as
oxidizing agent for obtaining the cleavage of the bond between the two carbon
atoms bearing the OH functions.
20 This reaction to cleave the double bond of unsaturated fatty acids has also
been the subject of a university study by E. Santacesaria et al. "Oxidative
Cleavage of the Double Bond of Monoenic Fatty Chains in Two Steps: A New
Promising Route to Azelaic and Other Industrial Products" published in Ind. Eng.
Chern. Res. 2000, 39, 2766-2771, which analyzes the two oxidative cleavage
25 steps mentioned in European patent EP 0 666 838.
The point in common between virtually all the various schemes described is
a step of cleavage of the double bond of the unsaturated fatty acid by means of a
strong oxidizing agent, so as to go from a long-chain unsaturated fatty acid to two
reduced-chain saturated fatty molecules, one being a-w-bifunctional and the other
30 monofunctional.
WO 20101095575 peTIFR2011/052990
4
The double-bond oxidative cleavage reaction which results in the formation
of the acid function on the two carbons of the double bond is also in itself known. It
can be carried out using a wide range of strong oxidizing agents.
It can, for example, be carried out by means of a strong oxidizing agent
5 such as KMn04 in concentrated form and with heat. The oxidative cleavage can
also be obtained via a sulfochromic route or by using ammonium chlorochromate
as oxidizing agent. Angew. Chern. Int. Ed. 2000,39, pp. 2206-2224 describes the
oxidative cleavage of the double bond, either with a peracid combined with a
ruthenium-based catalyst, or with H202 combined with Mo-, W- or Re-based
10 catalysts.
However, the route which has most generally been used for decades is
ozonolysis. The latter can be carried out with methyl oleate by way of example, in
reductive form according to the following reaction:
H3C-(CH2h-CH=CH-(CH2h-COOCH3 + (03, H2) ~
15 HOC-(CH2h-COOCH3 + H3C-(CH2)rCOH
or in oxidative form according to the following reaction:
H3C-(CH2h-CH=CH-(CH2)rCOOCH3 + (03+ O2+ H20) ~
H3C-(CH2h-COOH + COOH-(CH2h-COOCH3
The function introduced will be of the aldehyde type if the cleavage is
20 carried out under reducing conditions and of the acid type if the cleavage is carried
out under oxidizing conditions.
The choice between the two ozonolysis variants is essentially linked to the
final product envisioned. The reaction processes with the formation of an ozonide
and the operating conditions of these reactions have been widely described in the
25 literature, in particular in the abovementioned articles.
The use of H202 as cleavage agent, already mentioned in patent
GB 743 491, has been the subject of relatively recent studies which were
mentioned above: WO 93/12064, EP 0 666 838, E. Santacesaria et ai,
WO 07/039481.
30 The problem is that of finding a process for synthesizing the saturated or
unsaturated heminitrile which is more efficient and/or less expensive than the prior
processes. As it happens, the applicant has discovered that the use of H202 as
WO 2010/095575
5
PCT/FR2011/052990
oxidative cleavage agent in at least one of the steps of the process, combined with
the use of an unsaturated nitrile as reagent, makes it possible to achieve
performance levels which are much higher than those obtained with the prior art
processes.
5 The subject of the present invention is therefore a process for synthesizing
a heminitrile of formula CN-(CH2)n-COOH or of formula CN-R'-COOH, in which
formulae n is between 4 and 13 (limits included) and R' represents an alkylene
radical comprising from 4 to 13 carbon atoms and from 0 to 2 (limits included)
double bonds, with said synthesis being carried out using a compound of
10 unsaturated fatty acid (including ester or glyceride) type of natural origin,
corresponding to the formula
(R1-CH=CH-[(CH2)q-CH=CH]m -(CH2)r-COO-)p-G
in which formula:
R1 is H, or an alkyl radical having from 1 to 11 carbon atoms comprising,
15 where appropriate, a hydroxyl function,
q is an index 0 or 1,
m and p are whole indices, m being 0, 1 or 2 and p being an integer
between 1 and 3 (limits included),
if p is 1, in this case, G is an H, an alkyl radical having from 1 to 11,
20 preferably from 2 to 11, carbon atoms, or a radical comprising two or three carbon
atoms, bearing one or two hydroxyl function(s),
if p is 2, in this case, G is the residue of a diol or of glycerol bearing a
hydroxyl function,
if p is 2, in this case, G is the residue of a diol or glycerol also bearing a
25 hydroxyl function,
if p is 3, in this case, G is the residue of glycerol,
r is a whole index between 4 and 13 (limits included),
with it being possible for the C=C double bonds in said formula to be in cis or trans
30 conformation
and
WO 2010/095575 PCT/FR2011/052990
6
with said process comprising a first step of ammoniation of the compound of
unsaturated fatty acid, ester or glyceride type, resulting in the corresponding
unsaturated nitrile, which nitrile is subjected, in a second step, to an oxidative
cleavage in two successive phases with the formation of intermediate compounds
5 of vicinal diol type, using H202 as oxidizing agent, in at least one of the two
phases, so as to result in said heminitrile.
Insofar as said compound of unsaturated fatty acid (including ester or
glyceride) type is of natural origin, it may contain small amounts of other
compounds, in particular of saturated fatty acid type of natural origin, as is the
10 case in an oil of natural origin. Consequently, the definition of the compound of
unsaturated fatty acid (including ester or glyceride) type also means a product
comprising said compound of unsaturated fatty acid (including ester or glyceride)
type of natural origin having the formula specified above. For example, in the case
of the synthesis, according to the present invention, of the corresponding
15 heminitrile (8-cyanooctanoic acid) from oleic oil as raw material of natural origin,
this oil, depending on its purity, can comprise, inter alia and in addition, to the
purely oleic major esters (including triglycerides), mixed minor esters of oleic acid
and of stearic (saturated acid corresponding to oleic) and palmitic (saturated acid
comprising 16 carbon atoms) acid. The limitation to the compound as defined
20 above (according to formula) as raw material is a particular case of the invention.
With regard to the terminology "between a and b" used above and for the
rest of the description of the invention, it generally means, unless otherwise
indicated, the inclusion of the limits a and b and is to be considered equivalent to
the expression "ranging from a to b", which expression may also be used.
25 The term "ester" means simple ester, the "glyceride" (mono-, di- or tri) being
considered to be a complex ester.
The heminitrile of formula CN-(CH2)n-COOH can be obtained from a
compound of unsaturated fatty acid type corresponding to the formula R1-CH=CH(
CH2)r-COOG, in which formula G is an H, an alkyl radical having from 1 to 11 and
30 preferably from 2 to 11 carbon atoms, or a radical comprising two or three carbon
atoms, bearing one or two hydroxyl function(s).
WO 20101095575
7
PCT/FR2011/052990
The heminitrile of formula CN-R'-COOH can be obtained from a compound
of unsaturated fatty acid type corresponding to the formula (R1-CH=CH-[(CH2)qCH=
CH]m -(CH2kCOO-)p-G, with R1, G, m, p, q and r being defined as above.
According to one particular case of the process described above, for p = 1,
5 G can be a methyl, which would correspond, in the case where said unsaturated
fatty acid is oleic acid, to a methyl oleate ester.
Said second step of oxidative cleavage can, where appropriate, be
preceded by an ethenolysis of said nitrile if it is desired to use an w-unsaturated
nitrile as substrate of the cleavage reaction. This use is of more particular
10 advantage in the preparation of w-amino acids as polyamide monomers. In this
case, the process according to the invention may comprise an intermediate step of
ethenolysis (or of cross metathesis with a light olefin) of the nitrile resulting from
said ammoniation step, so as to result in an w-unsaturated nitrile, this being before
the second step where said w-unsaturated nitrile is subjected to said oxidative
15 cleavage.
More particularly, this ethenolysis (or metathesis with a light olefin) can be
applied to the oleonitrile resulting from the ammoniation of an oleic acid
compound, such as oleic acid or ester or the corresponding glyceride. More
precisely, the oleonitrile as obtained in the first step can be used in the preparation
20 of 9-amino nonanoic acid (monomer of polyamide 9), either via the route
comprising the prior ethenolysis of the oleonitrile, or via the route of oxidative
cleavage directly on the oleonitrile, the latter route being simpler (without
ethenolysis or metathesis).
Since the ethenolysis of the nitrile of said fatty acid is in fact a metathesis
25 reaction of said nitrile in the presence of ethylene, it is also possible to carry out
this metathesis in the presence of propylene, of 1-butene or of 2-butene.
Preferably, this intermediate metathesis is carried out in the presence of ethylene
or of 1-butene, and more preferentially in the presence of ethylene (ethenolysis).
According to a more preferred embodiment, said process does not
30 comprise any intermediate step of ethenolysis or of metathesis in general, said
process consequently being simpler.
WO 20101095575
8
PCT/FR2011/052990
It is known, see in particular the abovementioned publication by
E. Santacesaria, that the reaction for oxidative cleavage of a double bond is
carried out in two phases. During the first phase, the double bond is oxidized,
which results in the formation of a vicinal diol. In the second phase, the carbon-
5 carbon bond between the two hydroxyl functions is broken, with the formation of,
on the one hand, a saturated or unsaturated acid and, on the other hand, a
heminitrile, it being possible for the unsaturated acid to be obtained in particular in
the case where the feedstock comprises polyunsaturated fatty acids. More
precisely, in the latter case of polyunsaturated fatty acids, depending on the
10 position of the double bond subjected to the oxidative cleavage, it is possible to
obtain, as product, either an unsaturated acid or an unsaturated heminitrile and
therefore, more probably, a mixture of the two. The reaction scheme with
oleonitrile by way of example is the following:
CH3-(CH2h-CH=CH-(CH2h-CN + oxidizing agent -+ CH3-(CH2h-CHOH-CHOH-
15 (CH2h-CN
CH3-(CH2h-CHOH-CHOH-(CH2h-CN + oxidizing agent -+ CH3-(CH2h-COOH +
COOH-(CH2h-CN
In the case of linoleonitrile, the reaction scheme is:
either
20 CH3-(CH2)4-CH=CH-CH2-CH=CH-(CH2)r-CN + oxidizing agent
CH3-(CH2)4-CHOH-CHOH- CH2-CH=CH-(CH2h-CN
and
CH3-(CH2)4-CHOH-CHOH- CH2-CH=CH-(CH2)r-CN+ oxidizing agent -+
CH3-(CH2)4-COOH + HOOC-CH2-CH=CH-(CH2)r-CN
25 or
CH3-(CH2)4-CH=CH-CH2-CH=CH-(CH2h-CN + oxidizing agent -+
CH3-(CH2)4-CH=CH- CH2-CHOH-CHOH-(CH2)rCN
and
CH3-(CH2)4-CH=CH- CH2-CHOH-CHOH-(CH2h-CN+ oxidizing agent -+
30 CH3-(CH2)4-CH=CH-CH2-COOH + HOOC- CH2h-CN
And the final product is a mixture of the two heminitriles. When the feedstock
comprises polyunsaturated acids, i.e. when m is not zero (when m is equal to 1 or
WO20101095575 PCT/FR2011/052990
9
2) and one of the heminitriles corresponds to the general formula mentioned
above and with n = r + (q+2)*m, in this case, a hydrogenation of C=C double
bond(s) must be carried out during a subsequent or prior step. This hydrogenation
may be carried out in particular after the formation of a vicinal diol so as to force
5 the oxidative cleavage to take place in a single position or at the same time as the
hydrogenation of the nitrile function to an amine function.
In this variant of the process, with polyunsaturated nitriles, the first oxidation
phase can also result in the partial formation of two vicinal diols, which can in the
end lead to the formation of by-products such as short diacids.
10 According to varied embodiments of the invention, the following cases are
possible:
the heminitrile of formula CN-(CH2)n-COOH is obtained from a compound of
unsaturated fatty acid type corresponding to the formula R1-CH=CH-(CH2k
COOG, in which G is an H, an alkyl radical having from 1 to 11 and
15 preferably from 2 to 11 carbon atoms, or a radical comprising two or three
carbon atoms and bearing one or two hydroxyl function(s);
the heminitrile of formula CN-R'-COOH is obtained from a compound of
unsaturated fatty acid type corresponding to the formula (R1-CH=CH[(
CH2)q-CH=CH]m -(CH2)r-COO-)p-G, with G, R1, m, p, q and r as defined
20 above.
The process of the invention can be carried out according to several other
variants.
According to a first variant, the first phase of the second step is carried out
using H202 as oxidizing agent in the presence of a catalyst and the second phase
25 of oxidative cleavage is carried out by oxidation with pure or diluted oxygen and/or
with air as oxidizing agent (the oxidizing agent being molecular oxygen O2 in both
cases), optionally in the presence of a second catalyst.
According to a second variant, the first phase is carried out using H202 as
oxidizing agent in the presence of a catalyst and the second phase of oxidative
30 cleavage is carried out in a second reactor by oxidation by means of H202 as
oxidizing agent, optionally in the presence of another catalyst.
WO 2010/095575 PCT/FR2011/052990
10
According to a third variant, the two phases are carried out successively in
a single reaction medium and using H20 2 as oxidizing agent in the presence of a
single catalyst. WO 93/12064 describes a process using H20 2 as sole oxidizing
agent for synthesizing a diacid from an unsaturated fatty acid. This process
5 requires the use of a phase-transfer agent.
According to a fourth variant, the two phases are carried out successively in
a reactor comprising two zones: the first zone being fed with H20 2 as oxidizing
agent and in the presence of a first catalyst, and the second zone being fed with
O2 (air or oxygen) as oxidizing agent and in the presence of a second catalyst, the
10 reaction medium being moved from one zone to the other by any suitable means.
Thus, the first phase of said second step (oxidation) resulting in the vicinal
diols can be carried out by oxidation of a double bond or double bonds in the
presence of H20 2 as oxidizing agent, in the presence of an oxidation catalyst.
The expression "compound of natural unsaturated fatty acid type" is
15 intended to mean an acid or the corresponding unsaturated fatty ester (including
glyceride) derived from the plant or animal environment, including algae, more
generally derived from the plant kingdom and therefore renewable. This acid
compound comprises at least one olefinic unsaturation, located in position x
relative to the acid group (delta x) and comprises between 7 and 24 (limits
20 included) carbon atoms per molecule. This acid compound can be employed after
hydrolysis of natural oils, but also directly in the form of glycerides.
These various acid compounds are derived from vegetable oils extracted
from various oleagineous plants, such as sunflower, rape, castor oil plant,
Lesquerella, Camelina, olive, soya, palm tree, Sapindaceae, in particular avocado,
25 sea buckthorn, coriander, celery, dill, carrot, fennel, mango or Limnanthes alba
(meadowfoam), from microalgae or from animal fats.
The location of the double bond makes it possible to determine the formula
of the final heminitrile and the acid compound will therefore be chosen according
to the heminitrile desired.
30 In order to obtain a heminitrile comprising 6 carbon atoms, petroselenic acid
(cis-6-octadecenoic acid), its derivative 6-heptenoic acid obtained by ethenolysis
WO 20101095575
11
PCT/FR2011/052990
and a-linolenoic acid (6,9,12-octadecatrienoic acid), which can be obtained, for
example, from coriander, will be used as raw material.
In order to obtain a heminitrile comprising 8 carbon atoms, cis-8-eicosenoic
acid, cis-5,8,11,14- eicosatrienoic acid (arachidonic acid) and ricinoleic acid, which
5 give, after dehydration, conjugated 8,1O-octadecadienoic acid, will be used as raw
material.
In order to obtain a heminitrile comprising 9 carbon atoms, use may be
made of a wide range of fatty acids, for instance caproleic (cis-9-decenoic) acid,
palmitoleic (cis-9-hexadecenoic) acid, myristoleic (cis-9-tetradecenoic) acid, oleic
10 (cis-9-octadecenoic) acid, 9-decenoic acid obtained by ethenolysis of an oleic
acid, for example, elaidic (trans-9-octadecenoic) acid, and ricinoleic (12-hydroxycis-
9-octadecenoic) acid, gadoleic (cis-9-eicosenoic) acid, linoleic (9-12octadecadienoic)
acid, rumenic (9-11-octadecadienoic) acid, conjugated linoleic
(9-11-octadecadienoic) acid. These acids can be obtained from sunflower, rape,
15 castor oil plant, olive, soya, palm tree, flax, avocado, seed buckthorn, coriander,
celery, dill, carrot, fennel and Limnanthes (meadowfoam).
In order to obtain a heminitrile comprising 10 carbon atoms, use will be
made of 10,12 conjugated linoleic acid (10-12-octadecadienoic acid) or 10undecylenic
acid obtained by thermal cracking of ricinoleic acid methyl ester.
20 In order to obtain a heminitrile comprising 11 carbon atoms, use may be
made of vaccenic (cis-11-octadecenoic) acid, gondoic (cis-11-eicosenoic) acid,
lesquerolic (14-hydroxy-cis-11-eicosenoic) acid, and cetoleic (cis-11-docosenoic)
acid which can be obtained from Lesquerella oil (Iesquerolic acid), from Camelina
sativa oil (gondoic acid), the oil of a plant of the family Sapindaceae, from fish fat
25 and from microalgae oils (cetoleic acid) by dehydration of 12-hydroxystearic acid
(12-HSA), itself obtained by hydration of ricinoleic acid (vaccenic acid and its trans
equivalent) and of conjugated linoleic acid (9,11-octadecadienoic acid), obtained,
for example, by dehydration of ricinoleic acid.
In order to obtain a heminitrile comprising 12 carbon atoms, use may be
30 made of (cis or trans) 12-octadecenoic acid obtained, for example, by dehydration
of 12-hydroxystearic acid (12-HSA), the 12-HSA being obtained, for example, by
hydration of ricinoleic acid, 10,12 conjugated linoleic acid (10,12-octadecadienoic
WO2010/095575 PCT/FR2011/052990
12
acid) or 12-tridecenoic acid obtained, for example, by thermal cracking of the ester
(in particular methyl ester) of lesquerolic acid.
In order to obtain a heminitrile comprising 13 carbons, use may be made of
erucic (cis-13-docosenoic) acid or brassylic (trans-13-docosenoic) acid which can,
5 for example, be obtained from erucic rape, Honesty or Crambe maritime (sea
kale), and (cis or trans) 13-eicosenoic acid obtained, for example, by dehydration
of 14-hydroxyeicosanoic acid, itself obtained by hydrogenation of lesquerolic acid.
In order to obtain a heminitrile comprising 14 carbon atoms, use may be
made of (cis or trans) 14-eicosenoic acid obtained, for example, by dehydration of
10 14-hydroxyeicosanoic acid (14-HEA), itself obtained by hydrogenation of
lesquerolic acid.
In order to obtain a heminitrile comprising 15 carbon atoms, use may be
made of nervonic (cis-15-tetracosoic) acid which can be obtained from Malania
oleifera and from Honesty (Lunaria annua, also known as Pope's coin or money
15 plant).
The acid compounds which are the most important in nature, in order of
importance, are those which give C9-unsaturated acids (unsaturated in position 9),
then C13-unsaturated acids and then C11-unsaturated acids, since they are the
most widely available.
20 One of the acids which is preferred, with gondoic acid and lesquerolic acid,
for obtaining a heminitrile comprising 11 carbon atoms, is vaccenic acid.
Preferably, the vaccenic acid is of natural origin, l.e. derived from the plant
or animal environment, including algae, more generally from the plant kingdom
and therefore renewable. Thus, according to one preferred embodiment, the
25 subject of the invention is a process for synthesizing a heminitrile from vaccenic
acid of natural origin, as compound of unsaturated fatty acid type (including ester
or glyceride derivatives).
The pathways described below make it possible to obtain a vaccenic acid of
renewable origin:
30 the vaccenic acid can be obtained directly from the plants, in particular by
extraction, from mango pulp, from sea buckthorn, from sea buckthorn oil or
from derivatives of animal origin such as butter.
WO2010/095575 PCT/FR2011/052990
13
The vaccenic acid can also be obtained by genetically modifying plants
such as safflower, camelina or else Arabidopsis thaliana as is described by
Nguyen et aI., in Plant Physiology, December 2010, vol. 154, pp 18971904.
5 The vaccenic acid can, finally, be obtained from genetically modified
bacteria or yeasts, for example Escherichia coli, as is described by
Mendoza et ai, in Journal of Bacteriology September 1982, pp 1608-1611.
A final route for obtaining vaccenic acid is dehydration or, respectively,
ammoniation of 12-hydroxystearic acid.
10 With regard to gondoic acid (cis 11-eicosenoic acid), it can be used, like
vaccenic acid and lesquerolic acid, preferably, for the preparation of undecanoic
heminitrile.
Preferably, when gondoic acid is used, it is of natural origin, i.e. of plant
origin (which includes algae) or of animal origin. In one preferred embodiment, the
15 subject of the invention is a process for oxidative cleavage of an unsaturated fatty
nitrile obtained from gondoicacid of natural origin, so as to obtain the
corresponding heminitrile.
The following routes make it possible to obtain a gondoic acid of natural
origin:
20 the gondoic acid (cis-11-eicosenoic) acid can be obtained directly from
plants, in particular by extraction, from Camelina (Camelina sativa) oil which
contains more than 15% of gondoic acid, from erucic acid-rich rapeseed oil,
from Crambe, from honesty which generally contains from 2% to 15% of
gondoic acid, from Alyssum maritimum (gondoic acid content of 41.8%),
25 from Selenia grandis (gondoic acid content of 58.5%) or from Marshallia
caespitosa (gondoic acid content of 43.9%).
The gondoic acid can also be obtained by genetically modifying plants such
as Camelina or else Arabidopsis thaliana.
The gondoic acid can be obtained from genetically modified bacteria or
30 yeasts for example Escherichia coli.
A final route for obtaining gondoic acid is hydrolysis of jojoba oil, which is in
fact a vegetable wax (called oil because the wax is liquid at ambient
WO20101095575 PCT/FR2011/052990
14
temperature). This vegetable wax (fatty ester) contains approximately 35%
by weight of gondoic acid. The hydrolysis thereof gives a mixture of fatty
acids containing gondoic acid (approximately 70% by weight of the fatty
acids) and long-chain fatty alcohols which are separated.
5 JP9-278706 and JP9-279179 describe processes for obtaining gondoic acid
of high purity from the hydrolysis of jojoba oil.
More particularly, the gondoic acid can be obtained via the following routes:
1) as described in the cited patents JP9-278706 and JP9-279179, from jojoba
oil. After hydrolysis of the oil and a first distillation, extraction is carried out
10 with urea and an acid fraction is obtained which is rich in gondoic acid and
also contains a few traces of erucic acid, preferably without any other
unsaturated acid.
2) From HEAR (High Erucic Acid Rapeseed) erucic rapeseed oil containing,
for example, from 5% to 15% of gondoic acid.
15 Crambe oil and Honesty oil can also, for example, be used.
3) From a rapeseed variety selected for its higher gondoic acid content, for
example harvested before total maturity of the plant, since the fatty-chain
elongation mechanism involves the intermediate production of higher
concentrations of gondoic acid in the plant.
20 4) From Camelina oil, rich in gondoic acid.
5) From other plants such as Alyssum maritimum rich in gondoic acid (gondoic
acid content of 41.8%), Selenia grandis (content of 58.5%), or Marshallia
caespitosa (content of 43.9%).
All the plants mentioned above and others in genetically modified varieties
25 can be used for providing gondoic acid-enriched oils.
For all the fatty acids mentioned above, both acids having a cis
conformation and acids having a trans conformation may be used.
Among the preferred acids (and derivatives) that can be used as raw
materials for the synthesis of the heminitriles of the invention, mention may be
30 made, for the C9 heminitriles, of oleic acid (or ester or glyceride derivative) and,
for the C11 heminitriles, of lesquerolic acid, vaccenic acid and gondoic acid,
WO 2010/095575 PCT/FR2011/052990
15
according to the process of the invention involving the oxidative cleavage of the
corresponding unsaturated nitrile.
Thus, the oxidative cleavage of oleonitrile results in the heminitrile of
nonanedioic acid (azelaic acid) which can be used in the preparation of 9-
5 aminononanoic acid, a monomer of polyamide 9 (Nylon 9), by hydrogenation of its
nitrile function and conversion thereof to an amine function.
The oxidative cleavage of the nitriles of lesquerolic acid, of vaccenic acid
and of gondoic acid results, in the three cases, in the heminitrile of undecanedioic
acid, which, via the hydrogenation of its nitrile function and conversion thereof into
10 an amine function, can be used in the preparation of 11-aminoundecanoic acid, a
monomer of polyamide 11 (Nylon 11).
Preferably, the process of the invention uses oleic acid, lesquerolic acid,
vaccenic acid or gondoic acid of natural origin (renewable source), as unsaturated
fatty acid (or ester or glyceride derivative) used as starting raw material.
15 Thus, according to the process of the invention, the preferred nitrile used in
the second step is oleonitrile, the nitrile of lesquerolic acid, the nitrile of vaccenic
acid or the nitrile of gondoic acid.
According to one particular case, said unsaturated fatty acid of natural
origin involved in the process according to the invention is oleic acid or a
20 corresponding ester or glyceride.
According to another particular case, said unsaturated acid of natural origin
is gondoic acid (cis-11-eicosenoic acid) or a corresponding ester or glyceride.
Thus, the ammoniation of oleic acid (or ester or glyceride) results,
according to this process, via oxidative cleavage, in the C9 heminitrile, which can
25 be used to prepare the C9 amino acid (9-aminononanoic acid) by adding an
additional step of hydrogenation (of the nitrile function) to said process of the
invention.
In the same way, lesquerolic acid (14-hydroxy-11-eicosenoic acid),
vaccenic acid (cis 11-octadecenoic acid) and gondoic acid (cis-11-eicosenoic acid)
30 can result in the preparation of the C11 amino acid (11-aminoundecanoic acid),
always involving the oxidative cleavage of the unsaturated nitrile corresponding to
said unsaturated fatty acids, which cleavage is followed by the hydrogenation of
WO 2010/095575
16
PCT/FR2011/052990
the corresponding heminitrile. According to this process, for the C11 heminitrile,
vaccenic acid and gondoic acid are preferred, and vaccenic acid is even more
preferred.
The synthesis of nitriles from acids using ammonia is well known to those
5 skilled in the art. In this respect, reference may be made to the Kirk-Othmer
encyclopedia and to patent GB 741 739 already mentioned. The reaction scheme
can be summarized in the following way:
R-COOH + NH3 -+ [R-COO-NH4+] -+ [R-CONH2] + H20 -+ RCN + H20
This scheme applies just as much to natural fatty acids (esters) as to w-
10 unsaturated fatty acids.
The process can be carried out batchwise in the liquid or gas phase or
continuously in the gas phase. The reaction is carried out at high temperature and
above 250°C and in the presence of a catalyst which is generally a metal oxide,
and most commonly zinc oxide. The continuous elimination of the water formed,
15 while additionally carrying over the unreacted ammonia, enables rapid completion
of the reaction. Liquid-phase ammoniation is very suitable for long fatty chains
(comprising at least 10 carbon atoms). However, when operating with shorter
chain lengths, gas-phase ammoniation may become more suitable.
It is also known practice to carry out the ammoniation using urea or
20 cyanuric acid as ammoniation agent (see GB 641 955 already mentioned).
The difficult step is the cleavage. Indeed, the choice of the oxidizing agent
and of the fatty acid derivative subjected to this operation are essential for
obtaining good results. The choice of oxidizing agent falls on H202. It is an
inexpensive "green" oxidizing agent. It has many advantages over ozone (03) ,
25 oxygen (02) and the other strong oxidizing agents, such as permanganates,
periodates and other strong oxidizing agents. It is easy to handle, nontoxic, and
available in large amounts in liquid form. It is easier to use in the reaction since it
enables a moderate reaction temperature to be used, compared with 0 3, which
requires cold. In addition, it is possible to operate at a pressure close to
30 atmospheric pressure, whereas O2 requires working under pressure. Its oxidation
reaction, compared with those using O2or 0 3, exhibits a lower exothermicity and
allows good dissolution of the oxidizing agent in the medium. In addition, it needs
WO 2010/095575 PCT/FR2011/052990
17
only water as by-product, avoiding the presence of residues that are difficult to
treat (toxic osmium or period ate giving a halogenated compound or permanganate
or other strong oxidizing agent).
The amount of H202 introduced into the reaction medium is an important
5 factor. This amount is always at least equal to the stoichiometry of the reaction
under consideration (i.e. at least the stoichiometric amount - of H202). The first
phase of the (second) step of oxidative cleavage, resulting in the formation of the
vicinal diol, has a stoichiometry of 1 (1/1). The amount of H202injected is such that
the H202/unsaturated nitrile molar ratio is generally between 1/1 and 4/1 (limits
10 included). Thus, for the first phase of the oxidative cleavage step, H202 can be
injected into the medium in an amount representing from 1 to 4 molar equivalents
of the unsaturated nitrile to be oxidized, i.e. an HzOz/unsaturated nitrile molar ratio
ranging from 1 to 4, more particularly in the form of an aqueous solution having an
H202 content of between 30% and 70% (limits included) by weight, preferably
15 between 50% and 70% (limits included) by weight and more preferably between
60% and 70% (limits included) by weight, and preferably in the presence of a
catalyst consisting of tungsten derivatives, molybdenum derivatives or vanadium
derivatives, and more particularly chosen from tungstic acid (HZW04), the sodium
salt of this acid (Na2W04) combined with H3P04, molybdic acid (HzMo04) and its
20 sodium salt (Na2Mo04), heteropoly acids such as H3[PM012040], H4[SiM01204o],
H4[SiW12040], H3[PW1Z040] or (NH4)10[HzW1Z04Z], sodium metavanadate (Na3V04),
ammonium metavanadate ((NH4hV04), and their alkali metal salts.
When the second phase of the oxidative cleavage step also uses (like the
first phase) HzOz as oxidizing agent, according to the second and the third variant
25 of the process of the invention, in this case, the reaction for cleavage of the vicinal
diol formed has a stoichiometry of 3 (3/1). The amount of HzOz injected will then be
such that the H20z/vicinal diol molar ratio is between 3/1 and 10/1 (limits included).
Thus, the second phase of oxidative cleavage of the vicinal diols can be carried
out with H202 as agent for cleavage of the C-C bond between the vicinal
30 hydroxyls, injected in the form of an aqueous solution having an HZ02 content of
between 30% and 70% (limits included) by weight (or by mass), preferably
between 50% and 70% (limits included) by weight and more preferably between
WO2010/095575 PCT/FR2011/052990
18
60% and 70% (limits included) by weight, and such that the H202/vicinai diol molar
ratio is between 3/1 and 1011 (limits included).
For the third variant of the process according to the present invention,
wherein the reaction is carried out in one and the same reactor (one pot reaction),
5 the H202/unsaturated nitrile molar ratio is between 4/1 and 15/1 (limits included).
The aqueous hydrogen peroxide is introduced in the form of an aqueous
solution. The concentration of this solution is also to be taken into consideration,
and it is between 30% and 70% (limits included) by weight (by mass), preferably
between 50% and 70% (limits included) by weight and more preferably between
10 60% and 70% (limits included) by weight.
According to -one advantageous implementation variant of the process of
the invention, for a phase using H202 as oxidizing agent, the catalyst will be
introduced sequentially at the time the corresponding reaction phase is carried out.
Instead of introducing all of the catalysts into the reaction medium at the beginning
15 of the reaction, said catalyst will be introduced in small amounts throughout the
process, H202 for its part being introduced continuously. In one particularly
advantageous variant, H202 and the catalyst are introduced sequentially. It may
also be envisioned to continuously introduce the catalyst at a very low dose, like
H202, taking care, however, to avoid any prior contact between them. It is
20 therefore possible to carry out a sequential injection of the catalysts through the
course of the reaction process.
When the process is carried out with 02 as oxidizing agent for cleaving the
C-C bond between the two vicinal hydroxyls in the second phase of the second
step of the process of the invention, in this case, the amount of O2introduced will
25 be at least equal to the stoichiometry (stoichiometric amount) required for the
reaction, and preferably with an 02/vicinal diol molar ratio of between 3/2 and
10011 (limits included). In practice, it is possible to work with a very large excess of
air, for example by bubbling air into the medium, since it is not necessary for all
the oxygen to react, and thus to work at a low temperature in order to have better
30 control of the selectivity.
The catalysts that can be used for these two oxidative cleavage reactions
are generally known to those skilled in the art.
WO 2010/095575 PCT/FR2011/052990
19
The catalysts of the first phase preferably consist of tungsten derivatives,
molybdenum derivatives or vanadium derivatives. By way of example, mention
may be made of tungstic acid (HzW04), the sodium salt of this acid (NazW04)
combined with H3P04, molybdic acid (HzMo04) and its sodium salt (Na2Mo04),
5 heteropoly acids such as H3[PM01Z040], H4[SiM012040], H4[SiW12040], H3[PW12040]
or (NH4)10[HzW1204Z], sodium metavanadate (Na3V04) or ammonium
metavanadate ((NH4hV04). Generally, the alkali metal salts of the acids
mentioned above are also suitable.
Catalysts of this type will be used in the variant of the process carried out in
10 a single reactor with HZ02as oxidizing agent.
The amount of catalysts that are used in this first phase are generally
between 0.03% and 2% (limits included) by weight relative to the weight of nitrile
treated, and preferably between 0.5% and 2% (limits included) by weight.
During the second phase of cleavage of the vicinal diol using molecular
15 oxygen as oxidizing agent, it is possible to use catalysts based on cobalt, in the
form of cobalt acetate, such as Co(AchAH20, chloride or sulfate, or salts of Cu,
Cr, Fe or Mn, and also some of the catalysts used during the first phase such as
tungstic acid (H2W04) and its sodium salt Na2W04 and mixtures of the metals as
mentioned above, in particular ColW.
20 Thus, according to one particular embodiment of the process of the
invention, the second phase of said second step of oxidative cleavage of the
vicinal diols can be carried out with O2 as oxidizing agent for cleavage of the C-C
bond between said vicinal hydroxyls, more particularly in the presence of a
catalyst chosen from cobalt salts such as cobalt acetate (Co(AchAHzO), chloride
25 and sulfate or salts of Cu, Cr, Fe or Mn, and also the catalysts used during the first
phase, chosen from tungstic acid (H2W04) and its sodium salt Na2W04 and ColW
mixtures.
Even more particularly, in the second phase of the second step of the
process of the invention, the reaction can be carried out with O2as oxidizing agent
30 for cleavage of the C-C bond between the two vicinal hydroxyls and, in this case,
the amount of O2 introduced will be at least equal to the stoichiometry
(stoichiometric amount) required for said reaction, and preferably with an Oz/vicinal
WO 2010/095575 PCT/FR2011/052990
20
diol molar ratio of between 3/2 and 100/1 (limits included), and even more
preferably with the reaction being carried out at a temperature of between 20 and
80°C (limits included) and preferably between 40 and 70°C (limits included) and
even more particularly at a pressure of between 1 and 50 bar (limits included),
5 preferably between 1 and 20 bar (limits included) and more preferentially between
5 and 20 bar (limits included).
According to another particular variant of the process of the invention, said
second phase of oxidative cleavage of the vicinal diols is carried out with H20 2 as
oxidizing agent for cleaving the C-C bond between the vicinal hydroxyls and
10 preferably with said H20 2 being injected in the form of an aqueous solution having
an H20 2 content of between 30% and 70% (limits included) by weight (by mass),
preferably between 50% and 70% (limits included) by weight and more preferably
between 60% and 70% (limits included) by weight and with an HzOz/vicinal diol
molar ratio of between 3/1 and 10/1 (limits included).
15 The amounts of catalysts used in this second phase are between 0.1 mol%
and 3 mol% (limits included) relative to thediol treated, and preferably between
1 mol% and 2 mol% (limits included).
More particularly, according to the process of the invention, the catalysts
are injected sequentially through the course of the reaction process.
20 The second step of the process of the invention is carried out at a
temperature of between 20 and 80°C (limits included) and preferably between 40
and 70°C (limits included). The reaction can be carried out in a wide pressure
range, at a pressure of between 1 and 50 bar (limits included), preferably between
1 and 20 bar (limits included) and more preferably at a pressure approximately
25 equal to atmospheric pressure or slightly above atmospheric pressure and
between 1 and 5 bar (limits excluded). However, when the second phase of the
oxidative cleavage is carried out with molecular oxygen (02) , it is possible to use a
pressure which is higher than the pressure used during the first phase, and
generally between 5 and 20 bar (limits included).
30 According to one implementation variant of the process of the invention, two
separate reactors are used for implementing the second step, with one reactor for
the first phase and another for the second phase. In this case, it is advantageous
WO 2010/095575
21
PCT/FR2011/052990
to have recycling into the first-phase reactor of the diols formed at the end of this
phase. The degree of recycling is generally between 1% and 10% by weight (limits
included) relative to the starting nitrile entering the reaction. Thus, in this case, two
separate reactors are used for implementing the second step, and the effluent
5 resulting from the first phase (1st reactor) is subjected to a partial separation of the
aqueous and organic fractions, thus enabling the partial elimination of the aqueous
fraction and the recycling at the top of the first-phase (1st) reactor of a part of the
organic fraction, representing from 1% to 10% by weight of said unsaturated nitrile.
According to another variant of the process of the invention, use is made of
10 a single reactor with H20 2 as sole oxidizing agent for the two phases of the second
step and with the H20 2/nitrile molar ratio being between 4/1 and 10/1 (limits
included).
The heminitrile obtained at the end of the process can be used as a
substrate or raw material for synthesizing w-amino acids. The heminitrile is
15 subjected to a reaction for reduction with hydrogen of the nitrile function according
to the following reaction scheme in the case of the oleonitrile derivative:
HOOC-(CH2h-CN +2 H2-+ HOOC-(CH2h-CH2NH2
This reduction of the nitrile function to a primary amine and the obtaining of
w-amino fatty acids (esters), from heminitriles in the case in point, is well known to
20 those skilled in the art. The reduction step consists of a conventional
hydrogenation. Numerous catalysts can be used, but Raney nickel and Raney
cobalt will preferentially be used. In order to promote the formation of the primary
amine, the process is carried out with a partial ammonia pressure.
The heminitrile obtained at the end of the process can be used as a
25 synthesis substrate for synthesizing dinitrile by a subsequent reaction with
ammonia, according to the following reaction scheme:
CN-(CH2)n-COOH + NH3 -+ CN-(CH2)n-CN + 2 H20
This ammoniation of the acid function to a nitrile is well known to those
skilled in the art, see, in this respect, GB 741 739 already mentioned. The reaction
30 is carried out at high temperature, preferably above 250°C, and in the presence of
a catalyst which is generally a metal oxide and most commonly zinc oxide.
WO 2010/095575 PCT/FR2011/052990
22
The hydrogenated dinitrile results in a diamine which can be used in
numerous applications, including the preparation of polyamides, in particular in
combination with diacids.
The heminitrile obtained at the end of the process can be used as a
5 substrate for synthesizing diacid by hydrolysis of the nitrile function according to
the following reaction scheme:
CN-(CH2)n-COOH + 2 H20 -+ HOOC-(CH2)n-COOH + NH3
The hydrolysis is generally carried out under acid conditions.
The diacid can be used in numerous applications, including the preparation
10 of polyamides, in particular in combination with diamines.
In the first variant of the process, the first phase of oxidation of the nitrile is
carried out in a first reactor operating at a temperature of between 20 and 70°C
(limits included) and a pressure of between 1 and 5 bar (limits included), in the
presence of a catalyst consisting of tungstic acid or an equivalent catalyst, with an
15 amount of H202 of between 1 and 2 molar equivalents (i.e. from 1 to 2 mol of H202
per mole of compound treated), introduced in the form of an aqueous solution of
H202 with a content of between 35% and 70% by weight (limits included). At the
end of this first phase, where appropriate, after extraction of the water, the reaction
medium is transferred into a second reactor where it is subjected to oxidation with
20 O2 in the presence of a cobalt-based catalyst or an equivalent catalyst, at a
temperature generally of between 40 and 70°C (limits included) and at a pressure
of between 5 and 20 bar (limits included), with an excess of molecular oxygen.
When two separate reactors are used for implementing the second step,
the effluent resulting from the first phase can be subjected to a partial separation
25 of the aqueous and organic fractions, thus enabling the partial elimination of the
aqueous fraction and the recycling at the top of the first-phase reactor of a part of
the organic fraction representing from 1% to 10% by weight of the unsaturated
nitrile.
In the second variant, the first phase is carried out as in the first variant and
30 the second cleavage phase is carried out in a second reactor by oxidation by
means of H202 in the presence of tungstic acid or of another catalyst. At the end of
the first phase, the reaction medium can be subjected to an extraction of the
WO 20101095575 PCT/FR2011/052990
23
aqueous phase and also to a partial withdrawal of the organic phase for recycling
into the first-phase reactor. The temperature and pressure conditions during the
second phase are generally "milder" than in the first variant.
In the third variant, the two phases are carried out successively in a single
5 reactor, the reaction medium being oxidized with H202 in the presence of a single
catalyst generally consisting of tungstic acid or an equivalent catalyst. The amount
of H20 2 introduced is between 4 and 10 (limits included) molar equivalents (i.e.
from 4 to 10 mol of H202 per mole of nitrile) in the form of a solution with an H202
content of between 35% and 70% by weight (limits included). Thus, when a single
10 reactor is used for the two phases with H20 2 as sole oxidizing agent, the
H20 2/nitrile molar ratio can be between 4/1 and 10/1 (limits included).
In the fourth process variant, the two phases are carried out successively in
a reactor comprising two zones, the first being fed with H202 as oxidizing agent in
the presence of a first catalyst and the second with O2 (air) in the presence of a
15 second catalyst, said reactor being provided with means for moving the reaction
medium from the first-phase zone to the second-phase zone. The moving of the
reaction medium from one zone to the other can be carried out, for example, in a
rotating reactor of centrifuge type, a cone- or disk-shaped reactor, or any other
device for producing thin layers (thin films) of liquid.
20 By way of example in this respect, mention may be made of a Spinning
Disk Reactor as described in the technical documentation of the company
Protensive (Protensive Limited, BioScience Centre, International Centre for Life,
Times Square, Newcastle upon Tyne, NE1 4EP, United Kingdom), a Rotating
Packed Bed Reactor (Dow Chemical Company) or else reactors such as those
25 sold by the company Myers Vacuum, Inc. which are in the form of tanks which are
kept rotating. By way of example of equipment producing thin layers of liquid,
mention may be made of those described in Techniques de l'tnqenieur
[Techniques of the Engineer], number J2360-9 from 1988. In all these
technologies, the force of gravity is replaced with centrifugal force or with a
30 mechanical force in order to maintain a thin film of liquid and to thus promote gasliquid
matter transfer. This type of technology is particularly suitable for the present
process since the reaction media not found to be sensitive (the reaction is
WO 2010/095575 PCT/FR2011/052990
24
sensitive) not only to temperature variation, but also to the viscosity of the medium
(viscous media).
In the devices of centrifuge type, the first reaction phase is carried out in
proximity to the axis of rotation fed with substrate (fatty nitrile), catalyst (tungstic
5 acid) and H202 in an amount representing between 1 and 4 (limits included) mole
of H202 per mole of nitrile (molar equivalents), in aqueous solution at a content of
between 35% and 70% by weight (including limits), and the second phase is
carried out in proximity to the periphery of the device where excess O2 is injected,
the second-phase catalyst being, for its part, always introduced into a central zone
10 of the device. The final product of the reaction is recovered by overflowing at the
periphery. The reactors which may be suitable all provide a thin thickness of liquid
film, swept in countercurrent or concurrent mode with a gas stream containing
molecular oxygen.
The use of this type of device may also be advantageous in the variant of
15 the process wherein the oxidation phase is carried out with molecular oxygen in a
reactor independent of the first-phase reactor.
According to one more particular embodiment of the process as described
above according to the invention, said unsaturated fatty acid, used in the first step
to prepare said unsaturated nitrile of fatty acid, is prepared in a prior step of said
20 process, comprising the hydrogenation of a (suitable) corresponding starting
hydroxylated unsaturated fatty acid so as to obtain the corresponding
hydrogenated acid, said hydrogenation being followed by dehydration of said
hydrogenated acid. More particularly, this process applies to vaccenic acid as
unsaturated fatty acid, with the corresponding starting hydroxylated unsaturated
25 fatty acid being ricinoleic acid and the corresponding hydrogenated acid being 12hydroxystearic
acid (12-HSA).
The process of the invention, in addition to the manufacture of said
heminitrile, can be used directly or indirectly for preparing an w-amino acid
equivalent (corresponding) to said heminitrile, with said process comprising an
30 additional step of hydrogenation of the nitrile function of said heminitrile by
converting it into a corresponding amine function.
WO 2010/095575 PCT/FR2011/052990
25
According to this use, the process of the invention can result in the
preparation of 9-amino nonanoic acid from oleonitrile or in 11-aminoundecanoic
acid from the nitriles of lesquerolic acid or of vaccenic acid or of gondoic acid,
preferably from the nitriles of vaccenic acid or of gondoic acid and more
5 preferentially from the nitriles of vaccenic acid.
The process of the invention can also be used for preparing the diamines
and/or diacids corresponding to said heminitrile of the invention, thus obtained by
means of said method, as already described above. Thus, said diamines and/or
diacids can be used, like said w-amino acids, as monomers for obtaining
10 polyamides from raw materials which are of natural origin and from a renewable
source.
The preferred use of the process for preparing a heminitrile according to the
present invention relates to the preparation of polyamide monomers selected from
w-amino acids and/or the diamines and/or the diacids equivalent to said heminitrile
15 and/or also relates to the production of polyamides, by polymerization of said
monomers.
More particularly, said use relates to the preparation of a monomer which is
an w-amino acid equivalent to said heminitrile and said process comprising an
additional step of hydrogenation of the nitrile function of said heminitrile and the
20 conversion thereof into the corresponding amine function.
Even more specifically, this use results in the preparation of 9-amino
nonanoic acid from the oxidative cleavage of oleonitrile or results in 11-amino
undecanoic acid from the oxidative cleavage of the nitriles of lesquerolic acid or of
vaccenic acid or of gondoic acid, preferably from the oxidative cleavage of the
25 nitriles of vaccenic acid or of gondoic acid and more preferentially from the
oxidative cleavage of the nitriles of vaccenic acid.
Finally, the invention also covers a process for the manufacture of a
polyamide, which comprises the use of the process of the invention for preparing a
heminitrile from a starting unsaturated fatty acid, followed by the hydrogenation of
30 said heminitrile so as to obtain a corresponding ro-arnino acid and, finally, the
polymerization of said eo-amino acid so as to obtain said polyamide. Particularly
preferably, said manufacture is carried out using corresponding starting fatty acids
WO2010/095575
26
peTIFR2011/052990
(or ester or oil derivatives of said fatty acids) which are of natural origin and from a
renewable source. More particularly, according to this process, said polyamide is
preferably polyamide 9 and said corresponding starting fatty acid is oleic acid or
said polyamide is a polyamide 11 and said corresponding starting fatty acid is
5 vaccenic acid or lesquerolic acid or gondoic acid, preferably vaccenic acid or
gondoic acid and more preferentially vaccenic acid.
The process for preparing the heminitrile according to the invention is
illustrated by the examples which follow.
The analysis methods used are set out in the text hereinafter.
10 The composition of the organic phase is analyzed by gas chromatography
(GC) with an HP 5980 chromatograph.
The aqueous hydrogen peroxide content is analyzed using the Cefic
Peroxygens H202 AM7157 permanganate assay method. The iodine value is
determined according to standard NF EN 14111.
15 The viscosity is measured at 40°C with a Haake Viscotester VT550 with the
NV measuring device.
Examples 1 to 12
The tests described below illustrate the reaction for oxidation of oleonitrile
20 (ON) and also, by way of comparison, that of oleic acid (OA) and of methyl oleate
(MO) by means of aqueous hydrogen peroxide, of varying the reaction
parameters, l.e. the H202 content of the solution injected, and the injection molar
ratios and flow rates, at a constant set temperature (70°C) and under atmospheric
pressure.
25 100 g of fatty compound and 1.1 g of tungstic acid (H2W04; Merck 98%) are
introduced into a 250 ern" jacketed reactor comprising a mechanical stirrer, and
then stirred and heated at 70°C, said temperature being maintained by circulation
of thermostatic water. The aqueous hydrogen peroxide is then added in weight
contents which are variable according to the tests, via a peristaltic pump at
30 variable addition speeds according to the tests. The reaction is stopped after 6 h,
the aqueous phase is separated for analysis. The remaining organic phase is
WO20101095575 peTIFR2011/052990
27
washed several times with hot water until aqueous hydrogen peroxide has
disappeared from the washing water.
The fatty substrates introduced come from the following sources:
oleonitrile (ON): Arkema with C 16 :0: 3%, C 18:0: 9.7%, C18:1: 84.7%, C 18:Z: 1%
5 (% by weight).
oleic acid (OA): Oleon Radiacid 0210 (C18:1: 72%, C 18:Z: 9% by weight)
methyl oleate (MO): Aldrich Grade Technique (C18:1: 70% by weight)
The operating conditions and the results obtained are given in table 1
hereinafter, in which "molar ratio" denotes the Hz02/fatty compound molar ratio
10 and NA denotes the presence (Y) or the absence (N) of nonanoic acid,
characteristic of the cleavage of the molecule.
Table 1: operating conditions and results
Example Substrate [H202] Molar Flow rate Initial Final NA
No. (%) ratio g/min iodine iodine
value value
1 ON 50 6 0.24 98 4 Y
2 ON 50 4 0.48 98 30 Y
3 ON 50 6 0.48 98 41 Y
4 ON 35 4 0.34 98 37 N
5 ON 50 4 0.48 98 32 Y
6 MO 35 1.8 0.128 91 74 N
7 MO 50 4 0.48 91 80 N
8 MO 50 4 0.48 91 87 N
9 OA 35 1.8 0.128 86 9 N
10 OA 50 2.7 0.5 86 9 Y
11 OA 35 1.8 0.256 86 33 N
12 OA 50 6 0.48 86 26 Y
15 The oleonitrile oxidation reaction makes it possible to substantially reduce
the iodine value of the medium (see example 1) marking the disappearance of the
WO 2010/095575 peTIFR2011/052990
28
double bonds (formation of diols or cleavage). The H202 concentration has an
influence on the cleavage of the molecule treated (compare examples 1, 2, 3 and
5 with example 4) resulting in heminitrile formation.
The methyl oleate oxidation reaction results only in a very low conversion of
5 the double bonds regardless of the operating conditions. This oleic acid derivative
is not therefore suitable for the formation of diacids by oxidative cleavage.
The oleic acid oxidation reaction allows a reduction in the iodine value of
the medium (examples 9 to 12) and the formation of diacids, with a suitable H202
concentration.
10
Example 13
The oxidation of oleonitrile is an exothermic reaction which has an effect on
the temperature of the reaction medium over time. The monitoring of this
temperature, measured by thermocouple, makes it possible to have a better
15 understanding of the oxidation process.
The experiment was carried out' as follows by means of a reactor equipped
with its stirrer used in the previous examples. In a first phase, the temperature of
oleonitrile containing 1% by weight of H2W0 4 catalyst is increased by means of a
thermostatic bath at 70oe, and then two molar equivalents (2 mol per mole of
20 nitrile) of H20 2 in solution at 50% are injected over the course of 40 minutes by
means of a peristaltic pump. After these 40 minutes, in a second phase, the
injection is stopped for 60 minutes. The solution is left to separate by settling out
and the aqueous phase (with the majority of catalyst) is removed. Finally, at the
beginning of the third phase, 1% by weight of H2W0 4 catalyst is introduced and
25 4 molar equivalents (4 mol per mole of nitrile) of H20 2 in solution at 50% are
injected over the course of 10 minutes by means of the peristaltic pump. The
temperatures recorded in the reaction mixture throughout the reaction are given in
table 2 below.
30
WO 20101095575
29
Table 2: temperature
PCT/FR2011/052990
Time (min) 0 3 5 15 25 40 60 100 103 110
Toe 65.5 64.5 74.5 74 71 67.5 67 66 65.5 75
This example illustrates the advantage that can be gained from a sequence
injection of catalyst and of H202.
5
Example 14 - comparative
110 g of oleic acid (72% purity, containing 9% by weight of linoleic acid) and
1.1 g of tungstic acid are introduced into a 250 crrr' jacketed reactor comprising a
mechanical stirrer, and then stirred and heated at 40°C at atmospheric pressure.
10 77 9 of aqueous hydrogen peroxide (49% by weight) are then added via a
peristaltic pump at a speed of 0.92 cm3/min. The reaction is stopped after 24 h.
The aqueous phase is separated and analyzed. The organic phase is washed
several times with hot water until the aqueous hydrogen peroxide has disappeared
from the washed water.
15
Example 15 - according to the invention
92 9 of oleonitrile (85% purity, containing 10% by weight of octadecanitrile,
the nitrile of octadecanoic acid also known as stearic acid which is a saturated
compound) and 0.9 9 of tungstic acid are introduced into a 250 crrr' jacketed
20 reactor comprising a mechanical stirrer, and then stirred and heated at 40°C at
atmospheric pressure. 77 9 of aqueous hydrogen peroxide (at 49% by weight) are
added via a peristaltic pump at a speed of 0.95 cm3/min. The reaction is stopped
after 24 h. The aqueous phase is separated and analyzed. The organic phase is
washed several times with hot water until the aqueous hydrogen peroxide has
25 disappeared from the washed water.
The analysis results obtained are summarized in tables 3 to 6 below.
Table 3: H20 2content
WO 2010/095575
30
peTIFR2011/052990
% H202 by initial weight % H202 by weight after 24 h
Oleic acid 49 45
Oleonitrile 49 32
The aqueous hydrogen peroxide concentration of the aqueous phase,
initially 49% by weight, changes to 45% by weight after 24 h of reaction for oleic
acid and 32% by weight for oleonitrile. The amount of aqueous hydrogen peroxide
5 having reacted with the oleonitrile is substantially greater than that having reacted
with the acid. This means that there is a greater progression of the substrate
oxidation reaction, which is confirmed by the results of tables 4 to 6.
Iodine value:
10 The iodine value, which measures the concentration of double bonds, is
determined before and after the reaction.
Table 4: iodine value
Initial iodine value Iodine value after 24 h
(g 12/100 g of product) (g b/100 g of product)
Oleic acid 86 45
Oleonitrile 99 3
15 A clear decrease in the number of double bonds is noted in the case of
oleonitrile. The reaction between the aqueous hydrogen peroxide and the
oleonitrile, corresponding to the first phase of the process, progresses much more
quickly than the reaction between the oleic acid and H202.
20 GC (gas chromatography) analysis
The gas chromatography analysis of the organic phase after reaction is
carried out in order to determine the amount of nonanoic acid formed which shows
that the oxidation has reached the cleavage stage.
WO 2010/095575
31
Table 5: nonanoic acid analysis
PCT/FR2011/052990
Nonanoic acid (% by weight)
Oleic acid 0.04
Oleonitrile 0.2
The formation of nonanoic acid, a product resulting from the cleavage of the
fatty chain (second phase of the process), is observed. It is noted, in comparison
5 with oleic acid, that the concentration of nonanoic acid resulting from the cleavage
of oleonitrile is five times greater compared with that obtained with oleic acid.
Viscosity measurement
The viscosity 11 of the starting (initial) organic phase and also that obtained
10 after 24 h of reaction (final viscosity) are measured using, respectively, rotational
speeds of 245 S·1 and 972 S-1.
Table 6: viscosity
Rotational speed Initial viscosity Final viscosity
(S-1) (mPa.s) (mPa.s)
Oleic acid 245 24 110
Oleonitrile 245 7 82
Oleic acid 972 19 90
Oleonitrile 972 7 70
15 The results obtained show that the viscosity increases during the reaction.
However, it is noted that the viscosity of the organic phase obtained with oleic acid
is greater than the viscosity obtained with oleonitrile, although the reaction
between the aqueous hydrogen peroxide and the oleic acid is less advanced (see
tables 4 and 5).
20
wo2010/095575 PCT/FR2011/052990
32
Examples 16-20 with ammoniation of oleic acid and oxidation of the oleonitrile
obtained
Ammoniation of oleic acid in order to prepare oleonitrile
Approximately 2000 g of fatty acid (oleic) are charged to a 4-liter predried
5 glass reactor equipped with a mechanical stirrer, an electric heater, a
dephlegmator, a condenser, a dry-ice trap and a system for introducing ammonia.
A catalytic feedstock of zinc oxide (0.0625% of the weight of fatty acid) is added.
The reaction medium is stirred, and then heated to 200°C. Gaseous ammonia is
then introduced at a rate of 0.417 liters/min.Kg. The reaction medium is brought to
10 300°C. The introduction of ammonia is continued until the acid number of the
reaction medium is less than 0.1 mg of KOH/g. The duration of the reaction is
approximately 10 h.
At the end of the reaction, the reaction medium is cooled to 40°C and the
reactor is emptied.
15 The product is purified by distillation so as to obtain the oleonitrile, used
hereinafter.
Oxidative cleavage of oleonitrile
The oleonitrile as prepared above and tungstic acid (H2W04; Merck 98%)
20 are introduced into a 250 ml (100 ml for No. 20) jacketed reactor equipped with a
mechanical stirrer, and then stirred and heated at the temperature indicated in the
table. The temperature is maintained by circulation of thermostatic water. The
aqueous hydrogen peroxide is then added at various weight contents and at
various speeds according to the tests, via a peristaltic pump. The reaction is
25 stopped after the time indicated. The organic phase is separated and washed
several times with hot water until the aqueous hydrogen peroxide has disappeared
from the washing water. After drying of the organic phase under vacuum, the
composition is determined by gas chromatography (GC). The GC analyses are
carried out on an HP5890 series II instrument with an HP5 column and with an FlO
30 detector.
For the test of example 16, the aqueous hydrogen peroxide is added in the
following way: 48 g of H20 2 at 70% by weight in water are added, at a constant
WO 20101095575 PCT/FR2011/052990
33
flow rate over a period of approximately 45 min, to 150.4 g of oleonitrile containing
1.5 g of tungstic acid. After approximately 3 h, the aqueous phase is separated
and a further 48 g of H20 2 at 70% by weight in water are added, with the same
flow rate. This step is repeated again after 6 h, 21 h, 24 h and after 27 h, for an
5 overall duration of the test of 42 h and with the overall addition of 288 g of H20 2 at
70% by weight in water. At each addition of aqueous hydrogen peroxide, 1.2 g of
tungstic acid are added. Examples 19 and 20 were carried out with the reactor
maintained under a stream of nitrogen.
The conditions of examples 16 to 20 are summarized in table 7 below.
10
Table 7: operating conditions of examples 16 to 20
Example Composition Weight 0 Weight H202 T Total Weight End of
REF of oleonitrile oleonitrile H202 concentration CC) duration H2W04 addition
(g) atX% as X % by (h) (g) H202
in H2O weight (min)
(g)
16 1 150.4 288 70 70 42 * *
17 1 80.5 132 50 70 6 0.8 90
18 1 80.7 92 70 70 6 0.8 82
19 2 79.9 92 70 70 24 8.0 131
20 2 39.6 45 70 80 24 4.0 121
* see text (procedure above)
Two compositions (composition 1 and composition 2) were used with
15 regard to the oleic acid and the corresponding oleonitrile obtained. These
compositions are presented in table 8 below.
Table 8: Compositions 1 and 2 of the samples of oleic acid and of the
corresponding oleonitrile
20
• WO 2010/095575 peTIFR2011/052990
34
Component % by weight
Composition 1 Composition 2
C14:0 5.3 0.1
C16:1 - 0.2
C16:0 8.2 3.5
C18:1 68.6 82.7
C18:0 5.5 3.5
C18:2 4.8 0.5
C20:1 3.8 0.3
C20:0 3.8 0.2
The molar yield results, expressed as % of moles of product considered
relative to the number of moles of oleonitrile used at the start, are presented in
5 table 9 below.
Table 9: molar yield results
*Molar yield = mols product/mols oleonrtnle used at the start
*Molar yield (%)
Example REF Nonanoic acid 8-cyanooctanoic acid
16 45.8 43.3
17 10.4 9.3
18 12.4 5.9
19 42.4 40.8
20 46.9 53.3
..
10 Examples 21 and 22 with gondoic acid
Raw materials used (gondoic acid): A and B
A) The process is carried out as in patent JP 9-278706 (paragraphs 22 to 28)
using jojoba oil in order to obtain a 99% pure gondoic acid source;
WO2010/095575 PCT/FR2011/052990
5
B)
35
a mixture rich in gondoic acid is produced starting from erucic rapeseed oil.
After hydrolysis of the oil by saponification, then acidification, the fatty acids
are distilled in order to isolate, on the one hand, the oleic acid-rich light
acids and, on the other hand, the erucic acid-rich fraction. In doing so, a
third fraction rich in gondoic acid is produced. This fraction thus contains
1% of palmitic acid (C16:0), 11% of oleic acid (C18:1), 12% of linoleic acid
(C18:2), 50% of gondoic acid (C20:1), 3% of behenic acid (C20:0) and 12%
of erucic acid (C22:1).
10 Ammoniation of gondoic acid in order to prepare the corresponding nitrile
Approximately 2000 g of fatty acid (A or B) are charged to a 4-liter predried
glass reactor equipped with a mechanical stirrer, an electric heater, a
dephlegmator, a condenser, a dry-ice trap and a system for introducing ammonia.
A catalytic feedstock of zinc oxide (0.0625% of the weight of fatty acid) is added.
15 The reaction medium is stirred, and then heated to 200°C. Gaseous ammonia is
then introduced at a rate of 0.417 liters/min.Kg. The reaction medium is brought to
300°C. The introduction of ammonia is continued until the acid number of the
reaction media is less than 0.1 mg of KOH/g. The duration of the reaction is
approximately 10 h.
20 At the end of the reaction, the reaction medium is cooled to 40°C and the
reactor is emptied.
The product is purified by distillation in order to obtain the gondoic nitrile.
The nitrile obtained from sample A results in fewer heavy products than B.
The distillation makes it possible to eliminate the heavy products which form
25 during the conversion of the acid to nitrile, but also the residual amides formed.
Oxidative cleavage of the nitrile of gondoic acid
The nitriles resulting from the acids A or Band tungstic acid (H2W0 4; Merck
98%) are introduced into a 250 ml (100 ml for No. 20) jacketed reactor comprising
30 a mechanical stirrer, and then stirred and heated at the temperature indicated in
the table. The temperature is maintained by circulation of thermostatic water. The
aqueous hydrogen peroxide is then added at various weight contents and at
WO 2010/095575
36
PCT/FR2011/052990
various speeds according to the tests, via a peristaltic pump. The reaction is
stopped after the time indicated. The organic phase is separated and washed
several times with hot water until the aqueous hydrogen peroxide has disappeared
from the wash water. After drying of the organic phase under vacuum, the
5 composition is determined by gas chromatography (GC). The GC analyses are
carried out on an HP5890 series II instrument with an HP5 column and with an FlO
detector.
For example 21 (nitrile A), the aqueous hydrogen peroxide is added in the
following way: 15 g of H202 at 70% by weight in water are added, at a constant
10 flow rate over a period of approximately 45 min, to 80 g of nitrile A containing 1.5 g
of tungstic acid. After approximately 3 h, the aqueous phase is separated and a
further 15 g of H202 at 70% by weight in water are added, with the same flow rate.
This step is repeated again after 6 h, 21 h, 24 h and after 27 h, for an overall
duration of the test at 42 h and with the overall addition of 90 g of H202 at 70% by
15 weight in water. At each addition of aqueous hydrogen peroxide, 1.5 g of tungstic
acid are added. The tests were carried out with the reactor under a stream of
nitrogen. The test of example 22 with nitrile B is carried out under the same
conditions as the test of example 21 (see table 10 below).
20 Table 10: conditions of tests 21 and 22
Example Gondoic Weight Weight H202 T Total Weight
REF nitrile of H202 at concentration X (DC) duration H2W04
nitriles X%in (% by weight) (h) (g)
(g) H2O
(g)
21 A 80 90 70 70 42 9.0
22 B 80 90 70 70 42 9.0
The molar yield results are presented in table 11 below.
WO 20101095575
37
Table 11: molar yield results
PCT/FR2011/052990
Molar yield (%)
Example REF Nonanoic acid 1O-cyanodecanoic acid
21 (nitrile A) 38 36
22 (nitrile B) 35 33
The molar yield is calculated relative to the gondoic nitrile initially present
for 10-cyanodecanoic acid and relative to all the omega-9 fatty nitriles present in
5 the feedstock, for nonanoic acid.
Example 23, with hydrogenation of the heminitrile in order to obtain the
corresponding amino acid
Heminitrile: 10-cyanodecanoic acid (or cyano-10-decanoic acid)
10 Example 21 is reproduced while continuing the oxidation with H20 2 and
while renewing the aqueous phase with aqueous hydrogen peroxide at 70% and
with catalyst every 3 hours for a period of 48 h. At the end of this phase, the
aqueous phase is removed and the product recovered is first distilled under
vacuum in order to remove the pelargonic acid which has formed, and then the
15 product is recrystallized from acetic acid.
Hydrogenation of the heminitrile: obtaining 11-aminoundecanoic acid
An Ru/SiC catalyst is introduced into a stainless steel autoclave with a
capacity of 500 ml, equipped with an electromagnetic stirrer. A solution containing
20 2 g of 10-cyanodecanoic acid, obtained above in accordance with the invention,
and of mixed solvent composed of 140 ml of ethanol and 140 ml of aqueous
ammonia containing 28% by weight of ammonia, is introduced into the autoclave.
After having flushed the reactor several times with nitrogen, the reactor is
pressurized at 35 bar with hydrogen. The reactor is then heated to 110°C and the
25 stirring and the temperature are kept constant for 1.5 h. The reaction then no
longer consumes hydrogen and the autoclave drops in temperature to 70°C, and
then the pressure is reduced to atmospheric pressure and a colorless liquid is
WO2010/095575 PCT/FR2011/052990
38
withdrawn. The solvent is then evaporated off under vacuum at approximately
60°C and white crystals (1.2 g) of 11-undecanoic acid are recovered.

WO 2010/095575
39
Claims
PCT/FR2011/052990
1) A process for synthesizing a heminitrile of formula CN-(CH2)n-COOH or of
formula CN-R'-COOH, in which formulae n is between 4 and 13 (limits included)
5 and R' represents an alkylene radical comprising from 4 to 13 carbon atoms and
from 0 to 2 double bonds,
with said synthesis being carried out using a compound of unsaturated fatty acid
(including ester or glyceride) type of natural origin, corresponding to the formula
(R1-CH=CH-[(CH2)q-CH=CH]m -(CH2)r-COO-)p-G
10 in which formula:
R1 is H, or an alkyl radical having from 1 to 11 carbon atoms comprising,
where appropriate, a hydroxyl function,
q is an index 0 or 1,
m and p are whole indices, m being 0, 1 or 2 and p being between 1 and 3
15 (limits included),
if p is 1, in this case, G is an H, an alkyl radical having from 1 to 11,
preferably from 2 to 11, carbon atoms, or a radical comprising two or three carbon
atoms, bearing one or two hydroxyl function(s),
if p is 2, in this case, G is the residue of a diol or of glycerol bearing a
20 hydroxyl function,
if p is 3, in this case, G is the residue of glycerol,
r is a whole index between 4 and 13 (limits included),
with it being possible for the C=C double bonds in said formula to be in cis or trans
conformation and with said process comprising a first step of ammoniation of the
25 compound of unsaturated fatty acid, ester or glyceride type, resulting in the
corresponding unsaturated nitrile, which nitrile is subjected, in a second step, to an
oxidative cleavage in two successive phases with the formation of intermediate
compounds of vicinal diol type, using H20 2 as oxidizing agent, in at least one of
the two phases, so as to result in said heminitrile.
30 2) The process as claimed in claim 1, characterized in that the heminitrile of
formula CN-(CH2)n-COOH is obtained from a compound of unsaturated fatty acid
type corresponding to the formula R1-CH=CH-(CH2)r-COOG, in which formula G is
WO 2010/095575
40
PCT/FR2011/052990
an H, an alkyl radical having from 1 to 11 and preferably from 2 to 11 carbon
atoms, or a radical comprising two or three carbon atoms, bearing one or two
hydroxyl function(s).
3) The process as claimed in claim 1, characterized in that the heminitrile of
5 formula CN-R'-COOH is obtained from a compound of unsaturated fatty acid type
corresponding to the formula (R1-CH=CH-[(CH2)q-CH=CH]m -(CH2)r-COO-)p-G.
4) The process as claimed in one of claims 1 to 3, characterized in that the
first phase of the second step, resulting in the vicinal diols, is carried out by
oxidation of a double bond or double bonds using H202as oxidizing agent, in the
10 presence of an oxidation catalyst.
5) The process as claimed in claim 4, characterized in that H202 is injected
into the medium in an amount representing from 1 to 4 molar equivalents, l.e, from
1 to 4 mol of H202 per mole of unsaturated nitrile to be oxidized, more particularly
in the form of an aqueous solution having an H202 content of between 30% and
15 70% (limits included) by weight (by mass), preferably between 50% and 70%
(limits included) by weight and more preferably between 60% and 70% (limits
included) by weight, and preferably in the presence of a catalyst consisting of
tungsten derivatives, molybdenum derivatives or vanadium derivatives, more
particularly chosen from: tungstic acid (H2W04), the sodium salt of this acid
20 (Na2W04) combined with H3P04• molybdic acid (H2Mo04) and its sodium salt
(Na2Mo04), heteropoly acids such as H3[PM012040], H4[SiM012040], H4[SiW120 40],
H3[PW12040] or (NH4)1O[H2W12042], sodium metavanadate (Na3V04), ammonium
metavanadate «NH4hV04), and their alkaline metal salts.
6) The process as claimed in either of claims 4 and 5, characterized in that the
25 reaction of said second step is carried out at a temperature of between 20 and
ao°c (limits included) and preferably between 40 and 70°C (limits included) and
more particularly at a pressure of between 1 and 50 bar (limits included),
preferably at a pressure of between 1 and 20 bar (limits included) and more
preferably at a pressure substantially equal to atmospheric pressure (1 bar) or
30 slightly above atmospheric pressure and between 1 and 5 bar (limits not included).
7) The process as claimed in one of claims 4 to 6, characterized in that the
second phase of said second step, of oxidative cleavage of the diols, is carried out
• WO 2010/095575 PCT/FR2011/052990
41
with O2 as oxidizing agent for cleavage of the C-C bond between the vicinal
hydroxyls, in the presence of a catalyst chosen from cobalt salts such as in the
form of acetate (Co(AchAH20), chloride or sulfate or salts of Cu, Cr, Fe or Mn,
and also the catalysts used during the first phase, chosen from tungstic acid
5 (H2W04) and its sodium salt Na2W04and Co/W mixtures.
8) The process as claimed in claim 7, characterized in that the amount of O2
introduced is at least equal to the stoichiometric amount of the reaction, the
02/vicinal diol molar ratio preferably being between 3/2 and 100/1 (limits included),
and more particularly the reaction being carried out at a temperature of between
10 20 and 80°C (limits included) and preferably between 40 and 70°C (limits included)
and even more particularly at a pressure of between 1 and 50 bar (limits included),
preferably between 1 and 20 bar (limits included) and more preferentially between
5 and 20 bar (limits included).
9) The process as claimed in one of claims 4 to 6, characterized in that the
15 second phase of oxidative cleavage of the vicinal diols is carried out with H202 as
oxidizing agent for cleaving the C-C bond between the vicinal hydroxyls, preferably
with said H202 being injected in the form of an aqueous solution having an H202
content of between 30% and 70% (limits included) by weight (by mass), preferably
between 50% and 70% (limits included) by weight and more preferably between
20 60% and 70% (limits included) by weight and with an H202/vicinal diol molar ratio
of between 3/1 and 10/1 (limits included).
10) The process as claimed in one of claims 1 to 9, using two separate reactors
for implementing the second step, characterized in that the effluent resulting from
the first phase is subjected to a partial separation of the aqueous and organic
25 fractions, allowing the partial elimination of the aqueous fraction and the recycling,
at the top of the first-phase reactor, of a part of the organic fraction, representing
from 1% to 10% by weight of said unsaturated nitrile.
11) The process as claimed in one of claims 1 to 10, characterized in that use is
made of a single reactor with H202 as sole oxidizing agent for the two phases, the
30 H20z/nitrile molar ratio being between 4/1 and 10/1 (limits included).
• WO 2010/095575 PCT/FR2011/052990
42
12) The process as claimed in one of claims 1 to 11, characterized in that a
sequential injection of the catalysts is carried out through the course of the
reaction process.
13) The process as claimed in one of claims 1 to 12, characterized in that it
5 uses oleic acid or lesquerolic acid or vaccenic acid or gondoic acid, of natural
origin, as unsaturated fatty acid.
14) The process as claimed in one of claims 1 to 13, characterized in that it
comprises an intermediate step of metathesis of the nitrile resulting from said
ammoniation step, so as to result in an unsaturated nitrile before the second step
10 where said unsaturated nitrile is subjected to said oxidative cleavage so as to give
said heminitrile, said metathesis being carried out with ethylene (ethenolysis),
propylene, 1-butene or 2-butene, preferably with ethylene or 1-butene, more
preferentially with ethylene (ethenolysis).
15) The process as claimed in one of claims 1 to 13, characterized in that it
15 comprises an intermediate step of ethenolysis of the nitrile resulting from said
ammoniation step, so as to result in an w-unsaturated nitrile, this being before the
second step where said w-unsaturated nitrile is subjected to said oxidative
cleavage so as to result in said heminitrile.
16) The process as claimed in one of claims 1 to 15, characterized in that the
20 nitrile used in the second step is oleonitrile or the nitrile of lesquerolic acid or the
nitrile of vaccenic acid or the nitrile of gondoic acid.
17) The process as claimed in one of claims 1 to 16, characterized in that said
unsaturated fatty acid is prepared in a prior step of said process, comprising the
hydrogenation of a corresponding starting hydroxylated unsaturated fatty acid, so
25 as to obtain the corresponding hydrogenated acid, said hydrogenation being
followed by dehydration of said hydrogenated acid.
18) The process as claimed in claim 17, characterized in that said fatty acid is
vaccenic acid and in that said starting hydroxylated unsaturated fatty acid is
ricinoleic acid and in that said hydrogenated acid is 12-hydroxystearic acid (12-
30 HSA).
19) The use of the process as defined in anyone of claims 1 to 18,
characterized in that it relates to the preparation of polyamide monomers, selected
D
.. WO 2010/0955I5.-
43
PCT/FR2011/052990
•
from w-amino acids and/or the diamines and/or the diacids equivalent to said
heminitrile and/or in that said use relates to the production of polyamides.
20) The use as claimed in claim 19, characterized in that said monomer is an
co-amino acid equivalent to said heminitrile and that said process comprises an
5 additional step of hydrogenation of the nitrile function of said heminitrile and the
conversion thereof into the corresponding amine function.
21) The use as claimed in claim 20, characterized in that said process is as
defined in claim 16 and results in the preparation of 9-aminononanoic acid from
the oxidative cleavage of oleonitrile or in that said process is as defined in claim 16
10 or 18 and results in 11-aminoundecanoic acid from the oxidative cleavage of the
nitriles of lesquerolic acid or of vaccenic acid or of gondoic acid, preferably from
the oxidative cleavage of the nitriles of vaccenic acid or of gondoic acid and more
preferentially from the oxidative cleavage of the nitriles of vaccenic acid.
22) A process for the manufacture of a polyamide, characterized in that it
15 comprises the use of the process as defined in one of claims 1 to 18 for preparinq
a heminitrile from a starting unsaturated fatty acid, followed by the hydrogenation
of said heminitrile so as to obtain a corresponding co-amine acid and, finally, the
polymerization of said ro-arnino acid so as to obtain said polyamide.
23) The process as claimed in claim 22, characterized in that said manufacture
20 is carried out using corresponding starting unsaturated fatty acids (or ester or oil
derivatives of said fatty acids) which are of natural origin and from a renewable
source_.
24) The process as claimed in claim 22 or 23, characterized in that said
polyamide is:
25 polyamide 9 and said corresponding starting unsaturated fatty acid is oleic
acid,
polyamide 11 and said corresponding starting unsaturated fatty acid is
vaccenic acid or lesquerolic acid or gondoic acid, preferably vaccenic acid
or gondoic acid and more preferentially vaccenic acid.
....
Dated this 26/06/2013
.~~
NEHA SRIVASTAVA
OF REMFRY & SAGAR
ATTORNEY FOR THE APPLICANTS