POLYMORPHS OF
N- (2 -METHOXYBENZOYL) -4- [ (METHYLAMINOCARBONYL) AMINO] BENZENESULFONAMIDE
This invention relates to solid forms of N-acylsulfamoylphenylurea safeners, to
processes for their preparation, compositions comprising the solid forms and methods of
their use as safeners.
Herbicide safeners selectively protect crop plants from herbicide damage without
reducing activity in target weed species. They are used commercially to improve herbicide
selectivity between crop and weed species and can be applied, for example, as a mixture with
the herbicide or as a seed-treatment to the crop seed prior to sowing. US 5,215,570 discloses
that certain N-acylsulfamoylphenylurea derivatives can act as safeners. In particular the
compound of formula (I), N-(2-methoxybenzoyl)-4-[(methylaminocarbonyl)amino]
benzenesulfonamide, is disclosed:
This safener is suitable for protecting cultivated plants from the phytotoxic action of,
for example, acylcyclohexanedione herbicides, sulphonylurea herbicides, chloroacetanilide
herbicides and aryloxyphenoxypropionic acid herbicides.
New solid forms of this compound, their compositions and methods of their
preparation and use have now been discovered.
Accordingly, the present invention relates to novel crystalline forms of the safener of
formula (I).
In one aspect of the invention, there is provided a crystalline polymorph of the
compound of formula I, designated Form 1, which is characterised by a powder X-ray
diffraction pattern expressed in terms of 2Qangles, wherein the powder X-ray diffraction
pattern comprises at least three, at least four, at least five, at least six, at least 7 or all 2Q
angle values (in degrees) selected from the group comprising 7.4 ± 0.2, 9.3 ± 0.2, 11.7 ± 0.2,
12.0 ± 0.2, 14.3 ± 0.2, 15.1 ± 0.2, 17.4 ± 0.2 and 19.0 ± 0.2. These 2Qangle values are
derived from a powder X-ray diffraction pattern of polymorph Form 1 obtained using the
method of Example la. The values were generated using a wavelength of 1.54056A with a
2Qstep size of 0.02°.
In another aspect, the crystalline polymorph of the compound of formula I designated
Form 1 has a melting point of 198°C ± 5°C. This melting point is obtained using
Differential Scanning Calorimetry (DSC) with a heating rate of 10°C/minute.
In a further aspect of the invention, there is provided a crystalline polymorph of the
compound of formula I, designated Form 2, which is characterised by the unit cell
parameters of its single crystal as shown in Table 1. The polymorph was obtained using the
method of Example Id.
TABLE 1
In the table, a, b, c = Length of the edges of the unit cell; a, b , g = Angles of the unit
cell; and Z = molecules per cell.
Thus, in one aspect of the present invention, the crystalline polymorph of the
invention designated Form 2 has the following lattice parameters: a=19.38(5), b=7.34(5),
c=22.95(5), a = 90.00, b = 90.00, g = 90.00 and volume = 3264.8(5) A3.
In another aspect of the invention, the crystalline polymorph of the invention
designated Form 2 is characterised by a powder X-ray diffraction pattern expressed in terms
of 2Qangles, wherein the powder X-ray diffraction pattern comprises
(a) at least one 2Qangle value at 9.0 ± 0.2; and
(b) one 2Qangle value at 21.7 ± 0.2; and
(c) at least three, at least four, at least five, at least six or all 2Qangle values selected
from the group comprising 7.7 ± 0.2, 11.9 ± 0.2, 13.4 ± 0.2, 15.0 ± 0.2, 15.6 ±
0.2, 16.1 ± 0.2 and 18.0 ± 0.2.
In one embodiment, the crystalline polymorph of the invention designated Form 2 is
characterised by a powder X-ray diffraction pattern expressed in terms of 2Qangles, wherein
the powder X-ray diffraction pattern comprises
(a) at least one 2Qangle value at 9.0 ± 0.2; and
(b) one 2Qangle value at 21.7 ± 0.2; and
(c) at least three 2Qangle values selected from the group comprising 7.7 ± 0.2, 11.9 ±
0.2, 13.4 ± 0.2, 15.0 ± 0.2, 15.6 ± 0.2, 16.1 ± 0.2 and 18.0 ± 0.2.
In another embodiment, the crystalline polymorph of the invention designated Form 2
is characterised by a powder X-ray diffraction pattern expressed in terms of 2Qangles,
wherein the powder X-ray diffraction pattern comprises
(a) at least one 2Qangle value at 9.0 ± 0.2; and
(b) one 2Qangle value at 21.7 ± 0.2; and
(c) at least four 2Qangle values selected from the group comprising 7.7 ± 0.2, 11.9 ±
0.2, 13.4 ± 0.2, 15.0 ± 0.2, 15.6 ± 0.2, 16.1 ± 0.2 and 18.0 ± 0.2.
In another embodiment, the crystalline polymorph of the invention designated Form 2
is characterised by a powder X-ray diffraction pattern expressed in terms of 2Qangles,
wherein the powder X-ray diffraction pattern comprises
(a) at least one 2Qangle value at 9.0 ± 0.2; and
(b) one 2Qangle value at 21.7 ± 0.2; and
(c) at least five 2Qangle values selected from the group comprising 7.7 ± 0.2, 11.9 ±
0.2, 13.4 ± 0.2, 15.0 ± 0.2, 15.6 ± 0.2, 16.1 ± 0.2 and 18.0 ± 0.2.
In another embodiment, the crystalline polymorph of the invention designated Form 2
is characterised by a powder X-ray diffraction pattern expressed in terms of 2Qangles,
wherein the powder X-ray diffraction pattern comprises
(a) at least one 2Qangle value at 9.0 ± 0.2; and
(b) one 2Qangle value at 21.7 ± 0.2; and
(c) at least six 2Qangle values selected from the group comprising 7.7 ± 0.2, 11.9 ±
0.2, 13.4 ± 0.2, 15.0 ± 0.2, 15.6 ± 0.2, 16.1 ± 0.2 and 18.0 ± 0.2.
In another embodiment, the crystalline polymorph of the invention designated Form 2
is characterised by a powder X-ray diffraction pattern expressed in terms of 2Qangles,
wherein the powder X-ray diffraction pattern comprises
(a) at least one 2Qangle value at 9.0 ± 0.2; and
(b) one 2Qangle value at 21.7 ± 0.2; and
(c) all 2Qangle values selected from the group comprising 7.7 ± 0.2, 11.9 ± 0.2, 13.4
± 0.2, 15.0 ± 0.2, 15.6 ± 0.2, 16.1 ± 0.2 and 18.0 ± 0.2.
These 2Qangle values are derived from a powder X-ray diffraction pattern of
polymorph Form 2 obtained using the method of Example Id. The values are generated
using a wavelength of 1.54056A with a 2Qstep size of 0.02°.
In a further aspect, the crystalline polymorph of the invention designated Form 2 has
a melting point of 216°C ± 5°C. This melting point is obtained using Differential Scanning
Calorimetry (DSC) with a heating rate of 10°C/minute.
In a yet further aspect of the invention, there is provided a crystalline polymorph of -
the compound of formula I, designated Form 3, which is characterised by the unit cell
parameters of its single crystal as shown in Table 2. The polymorph was obtained using the
method of Example le.
TABLE 2
In the table, a, b, c = Length of the edges of the unit cell; a , b , g = Angles of the unit
cell; and Z = molecules per cell.
Thus, in one aspect of the present invention, the crystalline polymorph of the
invention designated Form 3 has the following lattice parameters: a=7.96(5), b=23.56(5),
c=9.1 1(5), a = 90.00, b = 92.58(5), g = 90.00 and volume = 1708.2(5) A3.
In another aspect of the invention, the crystalline polymorph of the invention
designated Form 3 is characterised by a powder X-ray diffraction pattern expressed in terms
of 2Qangles, wherein the powder X-ray diffraction pattern comprises
(a) one 2Qangle value at 16.9 ± 0.2; and
(b) one 2Qangle value at 18.9 ± 0.2; and
(c) at least three, at least four, at least five, at least six, at least seven, at least eight, at
least nine, at least ten or all 2Qangle values selected from the group comprising
7.5 ± 0.2, 12.3 ± 0.2, 13.4 ± 0.2, 14.4 ± 0.2, 14.9 ± 0.2, 15.8 ± 0.2, 18.3 ± 0.2,
20.9 ± 0.2, 21.9 ± 0.2, 22.6 ± 0.2 and 23.8 ± 0.2.
In one embodiment, the crystalline polymorph of the invention designated Form 3 is
characterised by a powder X-ray diffraction pattern expressed in terms of 2Qangles, wherein
the powder X-ray diffraction pattern comprises
(a) one 2Qangle value at 16.9 ± 0.2; and
(b) one 2Qangle value at 18.9 ± 0.2; and
(c) at least three 2Qangle values selected from the group comprising 7.5 ± 0.2, 12.3 ±
0.2, 13.4 ± 0.2, 14.4 ± 0.2, 14.9 ± 0.2, 15.8 ± 0.2, 18.3 ± 0.2, 20.9 ± 0.2, 21.9 ±
0.2, 22.6 ± 0.2 and 23.8 ± 0.2.
In another embodiment, the crystalline polymorph of the invention designated Form 3
is characterised by a powder X-ray diffraction pattern expressed in terms of 2Qangles,
wherein the powder X-ray diffraction pattern comprises
(a) one 2Qangle value at 16.9 ± 0.2; and
(b) one 2Qangle value at 18.9 ± 0.2; and
(c) at least six 2Qangle values selected from the group comprising 7.5 ± 0.2, 12.3 ±
0.2, 13.4 ± 0.2, 14.4 ± 0.2, 14.9 ± 0.2, 15.8 ± 0.2, 18.3 ± 0.2, 20.9 ± 0.2, 21.9 ±
0.2, 22.6 ± 0.2 and 23. 8 ± 0.2.
In another embodiment, the crystalline polymorph of the invention designated Form 3
is characterised by a powder X-ray diffraction pattern expressed in terms of 2Qangles,
wherein the powder X-ray diffraction pattern comprises
(a) one 2Qangle value at 16.9 ± 0.2; and
(b) one 2Qangle value at 18.9 ± 0.2; and
(c) at least nine 2Qangle values selected from the group comprising 7.5 ± 0.2, 12.3 ±
0.2, 13.4 ± 0.2, 14.4 ± 0.2, 14.9 ± 0.2, 15.8 ± 0.2, 18.3 ± 0.2, 20.9 ± 0.2, 21.9 ±
0.2, 22.6 ± 0.2 and 23.8 ± 0.2.
In another embodiment, the crystalline polymorph of the invention designated Form 3
is characterised by a powder X-ray diffraction pattern expressed in terms of 2Qangles,
wherein the powder X-ray diffraction pattern comprises
(a) one 2Qangle value at 16.9 ± 0.2; and
(b) one 2Qangle value at 18.9 ± 0.2; and
(c) all 2Qangle values selected from the group comprising 7.5 ± 0.2, 12.3 ± 0.2, 13.4
± 0.2, 14.4 ± 0.2, 14.9 ± 0.2, 15.8 ± 0.2, 18.3 ± 0.2, 20.9 ± 0.2, 21.9 ± 0.2, 22.6 ±
0.2 and 23.8 ± 0.2.
These 2Qangle values are derived from a powder X-ray diffraction pattern of
polymorph Form 3 obtained using the method of Example le. The values are generated
using a wavelength of 1.54056A with a 2Qstep size of 0.02°.
In another aspect, the crystalline polymorph of the invention designated Form 3 has a
melting point of 202°C ± 5°C. This melting point is obtained using Differential Scanning
Calorimetry (DSC) with a heating rate of 10°C/minute.
In the context of the present invention, a polymorph is a particular crystal form of a
chemical compound that can exist in more than one crystal form in the solid state. A crystal
form of a compound contains the constituent molecules arranged in orderly repeating
patterns extending in all three spatial dimensions (in contrast, an amorphous solid form has
no long-range order in the position of molecules). Different polymorphs of a compound
have different arrangements of atoms and or molecules in their crystal structure. When the
compound is a biologically active compound, such as a safener, the difference in crystal
structures can lead to different polymorphs having differing chemical, physical and
biological properties. Properties which may be affected include crystal shape, density,
hardness, colour, chemical stability, melting point, hydroscopicity, suspensibility, dissolution
rate and biological availability. As such, a specific polymorph may have properties which
make it more advantageous in a particular use relative to another polymorph of the same
compound: in particular, the physical, chemical and biological properties listed above can
have a significant effect on the development of production methods and formulations and the
quality and efficacy of plant treatment agents, such as safeners. It is noted that predicting
whether the solid state of a compound may be present as more than one polymorph is not
possible and nor is it possible to predict the properties of any of these crystal forms. In
particular, in the context of the present invention, it has been found that the compound of
formula (I) can exist as a stable polymorph designated Form 2 which is advantageous due to
its stability in comparison with Form 1 and Form 3 which decreases the amount of
crystallization occurring in formulations of the compound of formula (I) as the metastable
forms become, over time, the stable form. Such crystallization is detrimental because it can
lead to thickening and potentially solidification of the formulation and/or large crystals,
which can lead to blockages in application equipment e.g. in spray nozzles in agricultural
application machinery. As such, the polymorph designated Form 2 is preferred.
The present invention also relates to methods for the preparation of the polymorphs
of the invention either directly (i.e. not starting with other solid forms of the compound of
formula I) or by conversion of other solid forms of the compound of formula I .
Assaying the solid phase for the presence of crystals may be carried out by
conventional methods known in the art. For example, it is convenient and routine to use
powder X-ray diffraction techniques. Other techniques which may be used include
differential scanning calorimetry (DSC), thermogravimetric analysis (TGA) and Raman or
Infra-red spectroscopy, NMR, gas chromatography or HPLC. Single crystal X-ray
diffraction is especially useful in identifying crystal structures.
The polymorphs of the invention may be applied in unchanged form but are more
preferably incorporated into agrochemical compositions by conventional means.
Accordingly, in a further aspect, the invention provides an agrochemical composition
comprising a polymorph of the invention as defined above and at least one an agriculturally
acceptable carrier or diluent. In one embodiment, the composition of the invention further
comprises at least one herbicide. Preferably, the mixing ratio of the at least one herbicide to
safener is from 100:1 to 1:100, especially from 20:1 to 1:20.
In a further aspect, the present invention provides a method for protecting crops of
useful plants from the harmful effects of a herbicide, which comprises applying to the locus
of the useful plants the polymorphs of the invention.
In a still further aspect, the present invention provides a method for combating weeds
in crops of useful plants, which comprises treating the useful plants, seeds or cuttings thereof
or the locus of the useful plants simultaneously or at separate times with a herbicide and the
polymorphs of the invention.
Any method of application to weeds/crop of useful plant, or locus thereof, which is
routinely used in agriculture may be used, for example application by spray or broadcast
method typically after suitable dilution of the composition of the invention.
The term "plant" as used herein includes seedlings, bushes and trees.
The term "locus" as used herein includes not only areas where weeds may already be
growing, but also areas where weeds have yet to emerge, and also to areas under cultivation
with respect to crops of useful plants. Areas under cultivation include land on which the
crop plants are already growing and land intended for cultivation with such crop plants.
Crops of useful plants in which compositions of the invention may be used or the
methods of the invention applied include perennial crops, such as citrus fruit, grapevines,
nuts, oil palms, olives, pome fruit, stone fruit and rubber, and annual arable crops, such as
cereals, for example barley and wheat, cotton, oilseed rape, maize (including sweet corn),
rice, sorghum, soy beans, sugar beet, sugar cane, sunflowers, ornamentals and vegetables,
especially cereals and maize.
Compositions and methods of the invention may also be used on turf, pasture,
rangeland, rights of way etc. In particular they may be used on golf-courses, lawns, parks,
sports-fields, race-courses and the like.
Plants are to be understood as also including those which have been rendered tolerant
to herbicides or classes of herbicides (e.g. ALS-, GS-, EPSPS-, PPO- and HPPD-inhibitors)
by conventional methods of breeding or by genetic engineering. An example of a plant that
has been rendered tolerant to imidazolinones, e.g. imazamox, by conventional methods of
breeding is Clearfield® summer rape (canola). Examples of plants that have been rendered
tolerant to herbicides by genetic engineering methods include e.g. glyphosate- and
glufosinate-resistant maize varieties commercially available under the trade names
RoundupReady® and LibertyLink®.
Plants are also to be understood as being those which have been rendered resistant to
harmful insects by genetic engineering methods, for example Bt maize (resistant to European
corn borer), Bt cotton (resistant to cotton boll weevil) and also Bt potatoes (resistant to
Colorado beetle). Examples of Bt maize are the Bt 176 maize hybrids ofNK® (Syngenta
Seeds). Examples of transgenic plants comprising one or more genes that code for an
insecticidal resistance and express one or more toxins are KnockOut® (maize), Yield Gard®
(maize), NuCOTIN33B® (cotton), Bollgard® (cotton), NewLeaf® (potatoes), NatureGard®
and Protexcta®. Plants are also to be understood as being those which have been rendered
resistant to harmful insects by genetic engineering methods, for example Bt maize (resistant
to European corn borer), Bt cotton (resistant to cotton boll weevil) and also Bt potatoes
(resistant to Colorado beetle). Examples of Bt maize are the Bt 176 maize hybrids ofNK®
(Syngenta Seeds). Examples of transgenic plants comprising one or more genes that code for
an insecticidal resistance and express one or more toxins are KnockOut® (maize), Yield
Gard® (maize), NuCOTIN33B® (cotton), Bollgard® (cotton), NewLeaf® (potatoes),
NatureGard® and Protexcta®.Plant crops or seed material thereof can be both resistant to
herbicides and, at the same time, resistant to insect feeding ("stacked" transgenic events). For
example, seed can have the ability to express an insecticidal Cry3 protein while at the same
time being tolerant to glyphosate. Traits include those that increase plant defences against
insects, arachnids, nematodes and slugs and snails by virtue of toxins formed in the plants, in
particular those formed in the plants by the genetic material from Bacillus thuringiensis (for
example by the genes CrylA(Al), CrylA(b), CrylA(c), CryllA, CrylllA, CryIIIB2, Cry9c,
Cry2Ab, Cry3Bb and CrylF and also combinations thereof). Traits also include those that
plant defences against fungi, bacteria and viruses by systemic acquired resistance (SAR),
systemin, phytoalexins, elicitors and resistance genes and correspondingly expressed proteins
and toxins.
Plants or seed material thereof can be both resistant to herbicides and, at the same
time, resistant to insect feeding ("stacked" transgenic events). For example, seed can have the
ability to express an insecticidal Cry3 protein while at the same time being tolerant to
glyphosate.
Plants are also to be understood as being those which are obtained by conventional
methods of breeding or genetic engineering and contain so-called output traits (e.g. improved
storage stability, higher nutritional value and improved flavor).
Plants and plant cultivars obtained by genetic engineering methods, if appropriate in
combination with conventional methods, and parts thereof, may be treated by the
polymorphs and compositions of the invention. Plant cultivars are understood as meaning
plants having novel properties ("traits") which have been obtained by conventional breeding,
by mutagenesis or by recombinant DNA techniques. These can be cultivars, bio- or
genotypes. Depending on the plant species or plant cultivars, their location and growth
conditions (soils, climate, vegetation period, diet), the treatment according to the invention
may also result in superadditive "synergistic" effects. Thus, for example, reduced application
rates and/or a widening of the activity spectrum and/or an increase in the activity of the
substances and compositions which can be used according to the invention, better plant
growth, increased tolerance to high or low temperatures, increased tolerance to drought or to
water or soil salt content, increased flowering performance, easier harvesting, accelerated
maturation, higher harvest yields, higher quality and/or a higher nutritional value of the
harvested products, better storage stability and/or processability of the harvested products are
possible, which exceed the effects which were actually to be expected. The preferred
transgenic plants or plant cultivars (obtained by genetic engineering) which are to be treated
according to the invention include all plants which, by virtue of the genetic modification,
received genetic material which imparts particularly advantageous, useful traits to these
plants. Examples of such traits are better plant growth, increased tolerance to high or low
temperatures, increased tolerance to drought or to water or soil salt content, increased
flowering performance, easier harvesting, accelerated maturation, higher harvest yields,
higher quality and/or a higher nutritional value of the harvested products, better storage
stability and/or processability of the harvested products. Further examples of such traits are a
better defence of the plants against animal and microbial pests, such as against insects, mites,
phytopathogenic fungi, bacteria and/or viruses, and also increased tolerance of the plants to
certain herbicidally active compounds. Examples of transgenic plants which may be
mentioned are the important crop plants, such as cereals (wheat, rice), maize, soya beans,
potatoes, sugar beet, tomatoes, peas and other vegetable varieties, cotton, tobacco, oilseed
rape and also fruit plants (with the fruits apples, pears, citrus fruits and grapes), and
particular emphasis is given to maize, soya beans, potatoes, cotton, tobacco and oilseed rape.
The term "weeds" as used herein means any undesired plant, and thus includes not
only agronomically important weeds as described below, but also volunteer crop plants.
The compositions according to the invention are suitable for all the conventional
methods of application in agriculture, such as, e.g., pre-emergent application, post-emergent
application and seed dressing. Depending on the intended use, a polymorph of the invention
can be employed for pre-treatment of the seed of the crop plant (dressing of the seed or
cuttings) or can be introduced into the soil before or after sowing. However, it can also be
applied by itself or together with a herbicide before or after emergence of the plants. The
treatment of the plants or seed with the polymorph can therefore in principle be carried out
independently of the time of application of a herbicide. Treatment of the plants by
simultaneous application of the herbicide and a polymorph (e.g, as a tank mix) is as a rule
preferred. The application rate of polymorph to herbicide to be applied largely depends of
the method of use. For field treatment, as a rule 0.001 to 5.0 kg of polymorph/ha, preferably
0.01 to 0.5 kg polymorph/ha and as a rule between 0.005 to 2 kg of herbicide/ha, but
preferably between 0.001 to 1 kg/ha are applied. For seed dressing, in general 0.001 to 10 g
of polymorph/kg seed, preferably 0.05 to 2g polymorph/kg seed are applied.
The compositions of the invention (containing the polymorphs of the invention and
preferably a herbicide) are preferably formulated in various ways using using formulation
components, such as carriers, solvents and surface- active substances, for example, as
described hereinafter.
The formulated compositions can be in various physical forms. For compositions
containing the polymorphs of the invention but no herbicidal active ingredient, these can be
e.g. in the form of dusting powders, gels, wettable powders, water-dispersible granules,
water-dispersible tablets, effervescent pellets, aqueous dispersions, oily dispersions, suspoemulsions,
capsule suspensions, suspension concentrates, emulsifiable granules, impregnated
polymer films or in other forms known e.g. from the Manual on Development and Use of
FAO Specifications for Plant Protection Products, 5th Edition, 1999. Where one or more
herbicides are combined with the polymorph of the invention, these may be present in a
liquid or solid state: naming convention means that such formulations will be named
according to the presentation of the herbicidal active ingredient and not the polymorph of the
safener of compound I and so further formulation types are also possible. The formulated
compositions can be in the form of concentrates which are diluted prior to use, although
ready-to-use formulations can also be made. The dilutions can be made, for example, with
water, liquid fertilisers, micronutrients, biological organisms, oil or solvents.
The formulated compositions can be prepared e.g. by mixing the polymorph and
optional herbicide, with the formulation components in order to obtain compositions in the
form of finely divided solids, granules or dispersions. The active ingredients can also be
formulated with other components, such as finely divided solids, mineral oils, oils of
vegetable or animal origin, modified oils of vegetable or animal origin, organic solvents,
water, surface-active substances or combinations thereof. The active ingredients can also be
contained in very fine microcapsules consisting of a polymer. Microcapsules usually have a
diameter of from 0.1 to 500 microns. Typically, they will contain active ingredients in an
amount of about from 25 to 95% by weight of the capsule weight. The active ingredients can
be in the form of a monolithic solid or in the form of fine particles in solid or liquid
dispersion. The encapsulating membranes comprise, for example, natural or synthetic
rubbers, cellulose, styrene/butadiene copolymers, polyacrylonitrile, polyacrylate, polyesters,
polyamides, polyureas, polyurethane or chemically modified polymers and starch xanthates
or other known polymers. Alternatively, very fine microcapsules can be formed in which the
active ingredient is contained in the form of finely divided particles in a solid matrix of base
substance, but the microcapsules are not themselves encapsulated.
The formulation components that are suitable for the preparation of compositions
according to the invention are known per se. As liquid carriers there may be used: water,
toluene, xylene, petroleum ether, vegetable oils, acetone, methyl ethyl ketone,
cyclohexanone, acid anhydrides, acetonitrile, acetophenone, amyl acetate, 2-butanone,
butylene carbonate, chlorobenzene, cyclohexane, cyclohexanol, alkyl esters of acetic acid
(e.g. butyl acetate, ethyl acetate, isoamyl acetate, amyl acetate), diacetone alcohol, 1,2-
dichloropropane, diethanolamine, p-diethylbenzene, diethylene glycol, diethylene glycol
abietate, diethylene glycol butyl ether, diethylene glycol ethyl ether, diethylene glycol
methyl ether, N,N-dimethylformamide, dimethyl sulfoxide, 1,4-dioxane, dipropylene glycol,
dipropylene glycol methyl ether, dipropylene glycol dibenzoate, diproxitol, alkylpyrrolidone,
2-ethylhexanol, ethylene carbonate, 1,1,1-trichloroethane, 2-heptanone, alpha-pinene, dlimonene,
ethyl lactate, ethylene glycol, ethylene glycol butyl ether, ethylene glycol methyl
ether, gamma-butyrolactone, glycerol, glycerol acetate, glycerol diacetate, glycerol triacetate,
hexadecane, hexylene glycol, isobornyl acetate, isooctane, isophorone, isopropylbenzene,
isopropyl myristate, lactic acid, laurylamine, mesityl oxide, methoxypropanol, methyl
isoamyl ketone, methyl isobutyl ketone, methyl laurate, methyl octanoate, methyl oleate,
methylene chloride, m-xylene, n-hexane, n-octylamine, octadecanoic acid, octylamine
acetate, oleic acid, oleylamine, o-xylene, phenol, polyethylene glycol (PEG), propionic acid,
propyl lactate, propylene carbonate, propylene glycol, propylene glycol methyl ether, pxylene,
toluene, triethyl phosphate, triethylene glycol, xylenesulfonic acid, paraffin, mineral
oil, trichloroethylene, perchloroethylene, methanol, ethanol, isopropanol, and alcohols of
higher molecular weight, such as amyl alcohol, tetrahydrofurfuryl alcohol, hexanol, octanol,
N-methyl-2-pyrrolidone and the like. Water is generally the carrier of choice for diluting the
concentrates. Suitable solid carriers are, for example, talc, titanium dioxide, pyrophyllite
clay, silica, attapulgite clay, kieselguhr, limestone, calcium carbonate, bentonite, calcium
montmorillonite, cottonseed husks, wheat flour, soybean flour, pumice, wood flour, ground
walnut shells, lignin and similar substances, as described, for example, in CFR 180.1001. (c)
& (d).
A large number of surface-active substances may advantageously be used in the
formulations, especially in those formulations designed to be diluted with a carrier prior to
use. Surface-active substances may be anionic, cationic, non-ionic or polymeric and they can
be used as emulsifiers, wetting agents or suspending agents or for other purposes. Typical
surface-active substances include, for example, salts of alkyl sulfates, such as
diethanolammonium lauryl sulfate; salts of alkylarylsulfonates, such as calcium
dodecylbenzenesulfonate; alkylphenol/alkylene oxide addition products, such as nonylphenol
ethoxylate; alcohol/alkylene oxide addition products, such as tridecylalcohol ethoxylate;
soaps, such as sodium stearate; salts of alkylnaphthalenesulfonates, such as sodium
dibutylnaphthalenesulfonate; dialkyl esters of sulfosuccinate salts, such as sodium di(2-
ethylhexyl)sulfosuccinate; sorbitol esters, such as sorbitol oleate; quaternary amines, such as
lauryltrimethylammonium chloride, polyethylene glycol esters of fatty acids, such as
polyethylene glycol stearate; block copolymers of ethylene oxide and propylene oxide; and
salts of mono- and di-alkylphosphate esters; and also further substances described e.g. in
"McCutcheon's Detergents and Emulsifiers Annual" MC Publishing Corp., RidgewoodNew
Jersey, 1981.
Further components that can usually be used in such formulations include
crystallisation inhibitors, viscosity modifiers, suspending agents, dyes, anti-oxidants,
foaming agents, light absorbers, mixing auxiliaries, antifoams, complexing agents,
neutralising or pH-modifying substances and buffers, corrosion inhibitors, fragrances,
wetting agents, take-up enhancers, micronutrients, plasticisers, glidants, lubricants,
dispersants, thickeners, antifreezes, microbicides, and also liquid and solid fertilisers. An
example of such an adjuvant is ammonium sulphate.
The formulated compositions according to the invention can additionally include an
additive comprising an oil of vegetable or animal origin, a mineral oil, alkyl esters of such
oils or mixtures of such oils and oil derivatives. The amount of oil additive in the
composition according to the invention is generally from 0.01 to 10%, based on the spray
mixture. For example, the oil additive can be added to the spray tank in the desired
concentration after the spray mixture has been prepared. Preferred oil additives comprise
mineral oils or an oil of vegetable origin, for example rapeseed oil, olive oil or sunflower oil,
emulsified vegetable oil, such as AMIGO® (Rhone-Poulenc Canada Inc.), alkyl esters of oils
of vegetable origin, for example the methyl derivatives, or an oil of animal origin, such as
fish oil or beef tallow. A preferred additive contains, for example, as active components
essentially 80% by weight alkyl esters of fish oils and 15%> by weight methylated rapeseed
oil, and also 5% by weight of customary emulsifiers and pH modifiers. Especially preferred
oil additives comprise alkyl esters of C 22 fatty acids, especially the methyl derivatives of
C12-18 fatty acids, for example the methyl esters of lauric acid, palmitic acid and oleic acid,
being of importance. Those esters are known as methyl laurate (CAS-1 11-82-0), methyl
palmitate (CAS-1 12-39-0) and methyl oleate (CAS-1 12-62-9). A preferred fatty acid methyl
ester derivative is Emery ® 2230 and 2231 (Cognis GmbH). Those and other oil derivatives
are also known from the Compendium o f Herbicide Adjuvants, 5th Edition, Southern Illinois
University, 2000. Another preferred adjuvant is Adigor ® (Syngenta AG) which is a
methylated rapeseed oil-based adjuvant.
The application and action of the oil additives can be further improved by
combination with surface-active substances, such as non- ionic, anionic or cationic
surfactants. Examples of suitable anionic, non-ionic and cationic surfactants are listed on
pages 7 and 8 of W097/34485. Preferred surface-active substances are anionic surfactants
of the dodecylbenzylsulfonate type, especially the calcium salts thereof, and also non-ionic
surfactants of the fatty alcohol ethoxylate type. Special preference is given to ethoxylated
C12-22 fatty alcohols having a degree of ethoxylation of from 5 to 40. Examples of
commercially available surfactants are the Genapol types (Clariant AG). Also preferred are
silicone surfactants, especially polyalkyl-oxide-modified heptamethyltriloxanes which are
commercially available e.g. as Silwet L-77 ®, and also perfluorinated surfactants. The
concentration of the surface-active substances in relation to the total additive is generally
from 1 to 30% by weight. Examples of oil additives consisting of mixtures o f oil or mineral
oils or derivatives thereof with surfactants are Edenor ME SU®, Turbocharge ® (Syngenta
AG, CH) or ActipronC (BP Oil UK Limited, GB).
If desired, it is also possible for the mentioned surface-active substances to be used in
the formulations on their own, that is to say, without oil additives.
Furthermore, the addition of an organic solvent to the oil additive/surfactant mixture
may contribute to an additional enhancement of action. Suitable solvents are, for example,
Solvesso ® (ESSO) or Aromatic Solvent ® (Exxon Corporation). The concentration of such
solvents can be from 10 to 80% by weight of the total weight. Oil additives that are present
in admixture with solvents are described, for example, in US-A-4,834,908. A commercially
available oil additive disclosed therein is known by the name MERGE ® (BASF
Corporation). A further oil additive that is preferred according to the invention is SCORE
(Syngenta Crop Protection Canada).
In addition to the oil additives listed above, for the purpose of enhancing the action of
the compositions according to the invention it is also possible for formulations of
alkylpyrrolidones (e.g. Agrimax ®) to be added to the spray mixture. Formulations of
synthetic lattices, e.g. polyacrylamide, polyvinyl compounds or poly-l-p-menthene (e.g.
Bond ®, Courier® or Emerald ®) may also be used. It is also possible for solutions that contain
propionic acid, for example Eurogkem Pen-e-trate ®, to be added to the spray mixture as
action-enhancing agent.
Formulated compositions of the invention generally comprise from 0.1 to 99% by
weight, especially from 0.1 to 95% by weight, of the polymorph and a herbicide and from 1
to 99.9% by weight of a formulation adjuvant which preferably includes from 0 to 25% by
weight of a surface-active substance. Whereas commercial products will preferably be
formulated as concentrates, the end user will normally employ dilute formulations.
Various methods and techniques are suitable for using the polymorphs or
compositions containing them for protecting crop plants from the harmful actions of
herbicides, such as, for example, the following:
i) Seed dressing
Dressing of the seed with the polymorph formulated as a wettable powder by
shaking in a vessel until uniform distribution over the seed surface is achieved
(dry dressing). Aboutl to 500g of polymorph (4g to 2kg of wettable powder)
per 100 kg of seed are used here.
The dressing of the seed or the treatment of the sprouted seed are of course
the preferred methods of application, because the treatment with the
polymorph is directed entirely at the target crop. As a rule, 1 to lOOOg of
polymorph, preferably 5 to 250g of polymorph are used per 100 kg of seed, it
being possible to deviate upwards or downwards from the limit concentrations
stated (repeat dressing), depending on the methods, which also allows the
addition of other active compounds or micronutrients.
Application as a tank mix
A liquid processed mixture of polymorph and herbicide (reciprocal ratio of
amounts between 10:1 and 1:100) is used, the application rate of herbicide
being 0.005 to 5.0 kg per hectare. Such tank mixes are applied before or after
sowing.
Application into the seed furrow
The polymorph is introduced into the open sown seed furrow as a wettable
powder or as granules. After the seed furrow has been covered, the herbicide
is applied by the pre-emergent method in a conventional method.
iv) Controlled release of the polymorph
The polymorph is absorbed in solution on to mineral carrier granules or
polymerised granules (urea/formaldehyde) and dried. A coating which allows
the polymorph to be released over a certain period of time can optionally be
applied (coated granules).
In particular, preferred formulations have the following composition (% = per cent by
weight; active mixture of active compounds means the mixture of a compound of formula I
with a herbicide):
Dusts
Active mixture of active compounds: 0.1 to 10%, preferably 0.1 to 5%
Solid carrier: 99.9% to 90%, preferably 99.9 to 99%
Suspension concentrates
Active mixture of active compounds: 5 to 75%, preferably 10 to 50%
Water: 94 to 24%, preferably 88 to 30%
Surface-active agent: 1 to 40%, preferably 2 to 30%
Wettable powders
Active mixture of active compounds 0.5 to 90%, preferably 1 to 80%
Surface-active agent: 0.5 to 20%, preferably 10 to 15%
Solid carrier: 5 to 95%, preferably 15 to 90%
Granules
Active mixture of active compounds: 0.1 to 30%>, preferably 0.1 to 15%
Solid carrier: 99.5 to 70%, preferably 97 to 85%
Formulation examples for mixtures of the polymorph of the invention with a herbicides (%
=% by weight; EO = ethylene oxide)
Formulation 1. Wettable powders a) b) c) d)
active compound mixture 5% 25% 50% 80%
sodium lignosulfonate 4% - 3%
sodium lauryl sulphate 2% 3% - 4%
sodium diisobutylnaphthalene-sulfonate - 6% 5% 6%
octylphenol polyglycol ether (7-8 mol EO) - 1% 2%
highly dispersed silicic acid 1% 3% 5% 10%
kaolin 88% 62% 35% -
The active compound mixture is mixed thoroughly with the adjuvants and the resulting
mixture is thoroughly ground in a suitable mill, affording wettable powders which can be
diluted with water to give suspensions of any desired concentration.
Formulation 2. Coated granules a) b) c)
active compound mixture 0.1% 5% 15%
highly dispersed silicic acid 0.9% 2% 2%
inorganic carrier (diameter 0.1-1 mm) e.g. CaC0 3 or Si0 2 99.0% 93% 83%
The active compound mixture is dissolved in methylene chloride and applied to the carrier
by spraying, and the solvent is then evaporated off in vacuo.
Formulation 3. Coated granules a) b) c)
active compound mixture 0.1% 5% 15%
polyethylene glycol MW 200 1.0% 2% 3%
highly dispersed silicic acid 0.9%> 1% 2%
inorganic carrier (diameter 0.1-1 mm) e.g. CaC0 3 or Si0 2 98.0% 92% 80%
The finely ground active compound mixture is uniformly applied, in a mixer, to the carrier
moistened with polyethylene glycol. Non-dusty coated granules are obtained in this manner.
Formulation 4. Extruded granules a) b) c) d)
active compound mixture 0.1% 3% 5% 15%
sodium lignosulfonate 1.5% 2% 3% 4%
carboxymethylcellulose 1.4% 2% 2% 2%
kaolin 97.0% 93% 90% 79%
The active compound mixture is mixed and ground with the adjuvants, and the mixture is
moistened with water. The mixture is extruded and then dried in a stream of air.
Formulation 5. Dusts a) b) c)
active compound mixture 0.1% 1% 5%
talcum 39.9% 49% 35%
kaolin 60.0% 50% 60%
Ready-to-use dusts are obtained by mixing the active compound mixture with the carriers
and grinding the mixture in a suitable mill.
Formulation 6. Suspension concentrates a) b) c) d)
active compound mixture 3% 10% 25% 50%
ethylene glycol 5% 5% 5% 5%
nonylphenol polyglycol ether (15 mol EO) - 1% 2% -
sodium lignosulfonate 3% 3% 4% 5%
carboxymethylcellulose 1% 1% 1% 1%
37% aqueous formaldehyde solution 0.2 % 0.2% 0.2% 0.2%
silicone oil emulsion 0.8% 0.8% 0.8% 0.8 %
water 87% 79% 62% 38%
The finely ground active compound mixture is intimately mixed with the adjuvants, giving a
suspension concentrate from which suspensions of any desired concentration can be obtained
by dilution with water.
It is often more practical to formulate the polymorph and the herbicide individually
and then to bring them together as a 'tank mix' in water in the application equipment in the
desired mixing ratio shortly before application.
The compositions and formulations of the present invention can also be used in
combination with other active ingredients, e.g. other herbicides, and/or insecticides, and/or
acaricides, and/or nematocides, and/or moUuscicides, and/or fungicides, and/or plant growth
regulators. Such mixtures, and the use of such mixtures to control weeds and/or undesired
plant growth form yet further aspects of the invention.
Where a polymorph of the invention, in particular, the Form 2 polymorph, is
combined with at least one herbicide, the following herbicides are particularly preferred:
acetochlor, acifluorfen, acifluorfen-sodium, aclonifen, acrolein, alachlor, alloxydim, allyl
alcohol, ametryn, amicarbazone, amidosulfuron, aminocyclopyrachlor, aminopyralid,
amitrole, ammonium sulfamate, anilofos, asulam, atrazine, aviglycine, azafenidin,
azimsulfuron, BCPC, beflubutamid, benazolin, bencarbazone, benfluralin, benfuresate,
bensulfuron, bensulfuron-methyl, bensulide, bentazone, benzfendizone, benzobicyclon,
benzofenap, bicyclopyrone, bifenox, bilanafos, bispyribac, bispyribac-sodium, borax,
bromacil, bromobutide, bromophenoxim, bromoxynil, butachlor, butafenacil, butamifos,
butralin, butroxydim, butylate, cacodylic acid, calcium chlorate, cafenstrole, carbetamide,
carfentrazone, carfentrazone-ethyl, CDEA, CEPC, chlorflurenol, chlorflurenol-methyl,
chloridazon, chlorimuron, chlorimuron-ethyl, chloroacetic acid, chlorotoluron,
chlorpropham, chlorsulfuron, chlorthal, chlorthal-dimethyl, cinidon-ethyl, cinmethylin,
cinosulfuron, cisanilide, clethodim, clodinafop, clodinafop-propargyl, clomazone,
clomeprop, clopyralid, cloransulam, cloransulam-methyl, CMA, 4-CPB, CPMF, 4-CPP,
CPPC, cresol, cumyluron, cyanamide, cyanazine, cycloate, cyclosulfamuron, cycloxydim,
cyhalofop, cyhalofop-butyl, 2,4-D, 3,4-DA, daimuron, dalapon, dazomet, 2,4-DB, 3,4-DB,
2,4-DEB, desmedipham, desmetryn, dicamba, dichlobenil, ortho-dichlorobenzene, paradichlorobenzene,
dichlorprop, dichlorprop-P, diclofop, diclofop-methyl, diclosulam,
difenzoquat, difenzoquat metilsulfate, diflufenican, diflufenzopyr, dimefuron, dimepiperate,
dimethachlor, dimethametryn, dimethenamid, dimethenamid-P, dimethipin, dimethylarsinic
acid, dinitramine, dinoterb, diphenamid, dipropetryn, diquat, diquat dibromide, dithiopyr,
diuron, DNOC, 3,4-DP, DSMA, EBEP, endothal, EPTC, esprocarb, ethalfluralin,
ethametsulfuron, ethametsulfuron-methyl, ethephon, ethofumesate, ethoxyfen,
ethoxysulfuron, etobenzanid, fenoxaprop, fenoxaprop-P, fenoxaprop-ethyl, fenoxaprop-Pethyl,
fenoxasulfone, fentrazamide, ferrous sulfate, flamprop-M, flazasulfuron, florasulam,
fluazifop, fluazifop-butyl, fluazifop-P, fluazifop-P-butyl, fluazolate, flucarbazone,
flucarbazone-sodium, flucetosulfuron, fluchloralin, flufenacet, flufenpyr, flufenpyr-ethyl,
flumetralin, flumetsulam, flumiclorac, flumiclorac-pentyl, flumioxazin, flumipropin,
fluometuron, fluoroglycofen, fluoroglycofen-ethyl, fluoxaprop, flupoxam, flupropacil,
flupropanate, flupyrsulfuron, flupyrsulfuron-methyl-sodium, flurenol, fluridone,
flurochloridone, fluroxypyr, flurtamone, fluthiacet, fluthiacet-methyl, fomesafen,
foramsulfuron, fosamine, glufosinate, glufosinate-ammonium, glyphosate, halosulfuron,
halosulfuron-methyl, haloxyfop, haloxyfop-P, HC-252, hexazinone, imazamethabenz,
imazamethabenz-methyl, imazamox, imazapic, imazapyr, imazaquin, imazethapyr,
imazosulfuron, indanofan, indaziflam, iodomethane, iodosulfuron, iodosulfuron-methylsodium,
ioxynil, ipfencarbazone, isoproturon, isouron, isoxaben, isoxachlortole, isoxaflutole,
isoxapyrifop, karbutilate, lactofen, lenacil, linuron, MAA, MAMA, MCPA, MCPAthioethyl,
MCPB, mecoprop, mecoprop-P, mefenacet, mefluidide, mesosulfuron,
mesosulfuron-methyl, mesotrione, metam, metamifop, metamitron, metazachlor,
metazosulfuron, methabenzthiazuron, methazole, methylarsonic acid, methyldymron, methyl
isothiocyanate, metobenzuron, metobromuron, metolachlor, S-metolachlor, metosulam,
metoxuron, metribuzin, metsulfuron, metsulfuron-methyl, MK-616, molinate, monolinuron,
monosulfuron, monosulfuron-ester, MSMA, naproanilide, napropamide, naptalam, NDA-
402989, neburon, nicosulfuron, nipyraclofen, n-methyl glyphosate, nonanoic acid,
norflurazon, oleic acid (fatty acids), orbencarb, orthosulfamuron, oryzalin, oxadiargyl,
oxadiazon, oxasulfuron, oxaziclomefone, oxyfluorfen, paraquat, paraquat dichloride,
pebulate, pendimethalin, penoxsulam, pentachlorophenol, pentanochlor, pentoxazone,
pethoxamid, petrolium oils, phenmedipham, phenmedipham-ethyl, picloram, picolinafen,
pinoxaden, piperophos, potassium arsenite, potassium azide, pretilachlor, primisulfuron,
primisulfuron-methyl, prodiamine, profluazol, profoxydim, prohexadione-calcium,
prometon, prometryn, propachlor, propanil, propaquizafop, propazine, propham,
propisochlor, propoxycarbazone, propoxycarbazone-sodium, propyzamide, prosulfocarb,
prosulfuron, pyraclonil, pyraflufen, pyraflufen-ethyl, pyrasulfotole, pyrazolynate,
pyrazosulfuron, pyrazosulfuron-ethyl, pyrazoxyfen, pyribenzoxim, pyributicarb, pyridafol,
pyridate, pyriftalid, pyriminobac, pyriminobac-methyl, pyrimisulfan, pyrithiobac,
pyrithiobac-sodium, pyroxasulfone, pyroxulam, quinclorac, quinmerac, quinoclamine,
quizalofop, quizalofop-P, quizalo fop-ethyl, quizalofop-P-ethyl, rimsulfuron, saflufenacil,
sethoxydim, siduron, simazine, simetryn, SMA, sodium arsenite, sodium azide, sodium
chlorate, sulcotrione, sulfentrazone, sulfometuron, sulfometuron-methyl, sulfosate,
sulfosulfuron, sulfuric acid, tar oils, 2,3,6-TBA, TCA, TCA-sodium, tebutam, tebuthiuron,
tefuryltrione, tembotrione, tepraloxydim, terbacil, terbumeton, terbuthylazine, terbutryn,
thenylchlor, thiazafluron, thiazopyr, thifensulfuron, thiencarbazone, thifensulfuron-methyl,
thiobencarb, tiocarbazil, topramezone, tralkoxydim, triafamone, tri-allate, triasulfuron,
triaziflam, tribenuron, tribenuron-methyl, tricamba, triclopyr, trietazine, trifloxysulfuron,
trifloxysulfuron-sodium, trifluralin, triflusulfuron, triflusulfuron-methyl, trifop, trifopmethyl,
trihydroxytriazine, trinexapac-ethyl, tritosulfuron, [3-[2-chloro-4-fluoro-5-(lmethyl-
6-trifluoromethyl-2,4-dioxo-l,2,3,4-tetrahydropyrimidin-3-yl)phenoxy]-2-
pyridyloxy] acetic acid ethyl ester (CAS RN 353292-31-6), 4-amino-3-chloro-6-(4-chloro-2-
fluoro-3-methoxyphenyl)-2-pyridinecarboxylic acid (CAS RN 943832-60-8) and 4-hydroxy-
3-[[2-(3-methoxypropyl)-6-(difluoromethyl)-3-pyridinyl]carbonyl]-bicyclo[3 .2.1 ]oct-3-en-2-
one.
Particularly preferred combinations are the polymorph of Form 2 and ametryn,
atrazine, bicyclopyrone, cinosulfuron, clodinafop-propargyl, clomazone, dicamba,
dimethachlor, diquat, fluazifop-p-butyl, fomesafen, glyphosate, mesotrione, molinate,
napropamide, S-metolachlor, nicosulfuron, paraquat, pinoxaden, pretilachlor, primisulfuron,
prometryn, prosulfocarb, prosulfuron, pyridate, pyriftalid, tralkoxydim, triasulfuron and
trifloxysulfuron-sodium.
Whilst compositions comprising the polymorph of the invention and another
herbicide are explicitly disclosed above, the skilled man will appreciate that the invention
extends to three-way, and further multiple combinations comprising the above two-way
mixtures.
For the avoidance of doubt, even if not explicitly stated above, the mixing partners of
may also be in the form of any suitable agrochemically acceptable ester or salt, as mentioned
e.g. in The Pesticide Manual, Thirteenth Edition, British Crop Protection Council, 2003.
Various aspects and embodiments of the present invention will now be illustrated in
more detail by way of example and the following Figure in which:
FIGURE 1 shows the powder X-ray diffraction patterns of the polymorphs of N-(2-
methoxybenzoyl)-4-[(methylaminocarbonyl)amino] benzenesulfonamide named as Form 1,
Form 2 and Form 3, wherein the diffraction traces of Form 2 and 3 are those predicted from
the single crystal structure and that of Form 1 is obtained through powder X-ray diffraction
analysis.
FIGURE 2 shows the powder X-Ray diffraction patterns of (a) Form 2, (b) Form 3
and (c) 50°C slurry analysed after 2 days.
FIGURE 3 shows the powder X-Ray diffraction patterns of (a) Form 1, (b) Form 2,
(c) Form 3 and (d) 50°C slurry analysed after 2 days (e) 60°C slurry analysed after 2 days.
FIGURE 4 shows the powder X-Ray diffraction patterns of (a) Form 2, (b) 60°C
slurry analysed after 8 days and (c) 50°C slurry analysed after 8 days.
FIGURE 5 shows the powder X-Ray diffraction patterns of (a) Form 2 (b) Form 3,
(c) 60°C slurry analysed after 8 days and (d) 50°C slurry analysed after 8 days.
EXAMPLES
1. Preparation of Polymorphs
The compound of formula (I) was prepared as described in US 5,215,570.
l a Preparation of polymorph Form 1
The compound of formula (1) prepared as described in US 5,215,5070, is taken up in
ice water and the precipitated product is separated off and dried, yielding polymorph Form 1
lb. Preparation of polymorph Form 2
55ml of acetone was added to 4.6g of polymorph Form 1 and heated to reflux (56°C)
3mls of water was added to form a pale yellow solution which was allowed to cool slowly.
The resultant crystals were isolated by filtration and dried. DSC analysis confirmed the
presence of polymorph Form 2 with a melting point of 215°C.
lc. Seeded slurry conversion of Form 1 to Form 2
300g of polymorph Form 1 was stirred with 1500g 30% water/acetone and heated to
60°C. The slurry was seeded with 3g of polymorph Form 2. The conversion of Form 1 to
Form 2 was monitored by DSC - after 1 hour, Form 1 was not detected by DSC. The
crystals were collected by filtration under reduced pressure at 60°C, sucked dry on the filter
and then dried to constant weight in a vacuum oven at 40°C. The oven drying took 4 hours
and 200g polymorph Form 2 was produced with 97% purity (as assessed by DSC).
Id. Preparation of crystals of polymorph Form 2 for single crystal analysis
0.5g of polymorph Form 2 and 2g of 50% ethyl acetate/acetonitrile were mixed. The
resultant solution was left for 120 days. During this time, the solvent level dropped and
crystals became visible. The lid was removed from the vial and the remaining solvent
allowed to evaporate before the crystals were collected and analysed.
le. Preparation of polymorph Form 3
0.2g of polymorph Form 1 was dissolved in 15 to 20 mis of acetone at 45°C. Water
was added to give a water/acetone composition of 25% water. The resultant precipitate is
stirred at 45°C. Samples taken after 30 minutes showed the presence of polymorph Form 1.
Samples taken after 5, 7 and 20 days show the presence of polymorph Form 3.
2. Analysis of polymorphs
After preparation by the methods detailed above, the samples were subject to
analysis by powder X-ray diffraction and/or single crystal X-ray diffraction and/or
differential scanning calorimetry (DSC).
Powder X-ray diffraction analysis of solid material was carried out using the Briker
D8 powder diffractometer. Samples were mounted in Perspex sample holders and the
samples flattened. The sample holder was rotated and X-rays were collected from 4° to 34°
2-theta, with a scan time of 25 to 30 minutes depending on the pattern intensity.
Single crystal intensity data was collected on an Oxford Xcalibar PX Ultra
diffractometer using Cu Ka radiation ((l= 1.54056 A) with a graphite monochromator. The
crystal was mounted in NVH oil at room temperature for data collection. The data was
solved using the CRYSTALS software package.
DSC was carried out using a Mettler Toledo DSC 820 pr DSC1 . A sample loading of
around 5mg was used and this was heated from 25°C to 250°C at a rate of 10°C/minute on
the DSC820 or from 40°C to 250°C at a rate of 10°C/minute on the DSC1 . The lid of the
DSC crucible was pierced to allow the escape of any gas formed during the heating of the
sample.
3. Stability of Polymorphs
Approximately O.lg each of Form 1, Form 2 and Form 3 were added to 10ml of
ethanol at 50°C and 60°C until there were solids out of solution (a slurry). The temperature
was maintained with stirring and the crystal form examined after 2 and 8 days.
At 50°C and 60°C after 2 days, Form 2 and Form 3 were still present as seen in
Figure 1. There was no evidence of Form 1.
Further slurrying for 8 days in total showed complete conversion to Form 2 at both
temperatures, see Figure 3.
Although the invention has been described with reference to preferred embodiments
and examples thereof, the scope of the present invention is not limited only to those
described embodiments. As will be apparent to persons skilled in the art, modifications and
adaptations to the above-described invention can be made without departing from the spirit
and scope of the invention, which is defined and circumscribed by the appended claims. All
publications cited herein are hereby incorporated by reference in their entirety for all
purposes to the same extent as if each individual publication were specifically and
individually indicated to be so incorporated by reference.
A crystalline polymorph of the compound of formula I, which has the following lattice
parameters: a=19.38(5), b=7.34(5), c=22.95(5), a = 90.00, b = 90.00, g = 90.00 and
volume = 3264.8(5) A3.
The crystalline polymorph of claim 1, wherein the polymorph is characterised by a
powder X-ray diffraction pattern expressed in terms of 2Qangles, wherein the powder
X-ray diffraction pattern comprises:
(a) at least one 2Qangle value at 9.0 ± 0.2; and
(b) one 2Qangle value at 2 1.7 ± 0.2; and
(c) at least three 2Qangle values selected from the group comprising 7.7 ± 0.2, 11.9 ±
0.2, 13.4 ± 0.2, 15.0 ± 0.2, 15.6 ± 0.2, 16.1 ± 0.2 and 18.0 ± 0.2.
The crystalline polymorph of claim 1 or claim 2 which has a melting point of 216°C ±
5°C.
A crystalline polymorph of the compound of formula I, wherein the polymorph is
characterised by a powder X-ray diffraction pattern expressed in terms of 2Qangles,
wherein the powder X-ray diffraction pattern comprises:
(a) at least one 2Qangle value at 9.0 ± 0.2; and
(b) one 2Qangle value at 2 1.7 ± 0.2; and
(c) at least three 2Qangle values selected from the group comprising 7.7 ± 0.2, 11.9 ±
0.2, 13.4 ± 0.2, 15.0 ± 0.2, 15.6 ± 0.2, 16.1 ± 0.2 and 18.0 ± 0.2.
The crystalline polymorph of claim 4 which has a melting point of 216°C ± 5°C.
6. A crystalline polymorph of the compound of formula I which has the following lattice
parameters: a=7.96(5), b=23.56(5), c=9.1 1(5), a = 90.00, b = 92.58(5), g = 90.00 and
volume = 1708.2(5) A3.
7. The crystalline polymorph of claim 6, wherein the polymorph is characterised by a
powder X-ray diffraction pattern expressed in terms of 2Qangles, wherein the powder
X-ray diffraction pattern comprises
(a) one 2Qangle value at 16.9 ± 0.2; and
(b) one 2Qangle value at 18.9 ± 0.2; and
(c) at least three 2Qangle values selected from the group comprising 7.5 ± 0.2, 12.3 ±
0.2, 13.4 ± 0.2, 14.4 ± 0.2, 14.9 ± 0.2, 15.8 ± 0.2, 18.3 ± 0.2, 20.9 ± 0.2, 21.9 ±
0.2, 22.6 ± 0.2 and 23. 8 ± 0.2.
8. The crystalline polymorph of claim 6 or claim 7 which has a melting point of 202°C ±
5°C.
9. A crystalline polymorph of the compound of formula I wherein the polymorph is
characterised by a powder X-ray diffraction pattern expressed in terms of 2Qangles,
wherein the powder X-ray diffraction pattern comprises
(a) one 2Qangle value at 16.9 ± 0.2; and
(b) one 2Qangle value at 18.9 ± 0.2; and
(c) at least three 2Qangle values selected from the group comprising 7.5 ± 0.2, 12.3 ±
0.2, 13.4 ± 0.2, 14.4 ± 0.2, 14.9 ± 0.2, 15.8 ± 0.2, 18.3 ± 0.2, 20.9 ± 0.2, 21.9 ±
0.2, 22.6 ± 0.2 and 23.8 ± 0.2.
10. The crystalline polymorph of claim 9 which has a melting point of 202°C ± 5°C.
11. An agricultural composition comprising a polymorph as claimed in any one of claims 1
to 10 and at least one agriculturally acceptable carrier or diluent.
12. The composition of claim 11, which further comprises at least one herbicide.
13. A method for protecting crops of useful plants from the harmful effects of a herbicide,
which comprises applying to the locus of the useful plants a polymorph as claimed in
any one of claims 1 to 10 or a composition of claim 11 or claim 12.
14. A method for combating weeds in crops of useful plants, which comprises treating the
useful plants, seeds or cuttings thereof or the locus of the useful plants simultaneously
or at separate times with a herbicide and a polymorph as claimed in any one of claims
1 to 10.