CRYSTAL POLYMORPHISM OF HERBICIDES AND THEIR COMPOUNDS

Abstract

The invention relates to a crystalline polymorph of a compound of the formula (I): an agricultural composition containing this polymorph, and a method for weed control in crops that are useful plants.

Description

[0001] CRYSTALLINE FORMS OF A HERBICIDE AND THEIR COMPOSITIONS

[0002] The present invention relates to solid forms of 3-{2-chloro-4-fluoro-5-[3-methyl-2,6-dioxo-4- (trifluoromethyl)-l ,3-dihydro-1 -pyrimidinyl]phenyl}-5-methyl-4,5-dihydro-5-isoxazolecarboxylic acid ethyl ester, compositions comprising these novel solid forms, to the use thereof in herbicidal compositions, and their use in controlling plants or inhibiting plant growth.

[0003] Ethyl 3-[2-chloro-4-fluoro-5-[3-methyl-2,6-dioxo-4-(trifluoromethyl)pyrimidin-1 -yl]phenyl]-5-methyl-4H- isoxazole-5-carboxylate has the structure of formula (I), and is herein also referred to as “compound of formula (I)”.

[0004] The compound of formula (I) as well its preparation is disclosed, for example, in WO 2016 / 095768 and WO 2020 / 063613:

[0005] (I).

[0006] To date, this compound has only been isolated and disclosed as an amorphous material. While the compound in its amorphous form has successfully shown a broad spectrum herbicidal activity, it was found that its physical properties make it difficult to handle and weigh. Also, in order to prepare formulations, comminuting, in particular milling of the amorphous material often resulted in comparatively large particles, and a very broad particle size distribution, making a homogenous formulation and distribution difficult. In fact, in many cases, the amorphous form could not be milled and thus this amorphous form could not be tested further.

[0007] New solid forms of this compound, their compositions and methods of their preparation and use have now been discovered.

[0008] Accordingly, the present invention relates to novel crystalline forms of the compound of formula (I).

[0009] The novel crystalline forms of ethyl 3-[2-chloro-4-fluoro-5-[3-methyl-2,6-dioxo-4- (trifluoromethyl)pyrimidin-1 -yl]phenyl]-5-methyl-4H-isoxazole-5-carboxylate are characterized by a powder X-ray diffraction pattern expressed in terms of 20 angles.

[0010] These 20 angle values are derived from a powder X-ray diffraction pattern of the polymorphs are obtained using the method of Example 2, whereby the values are generated using a wavelength of 1 .54056A with a 20 step size of 0.02°. According to a first aspect of the invention, there is provided a novel crystalline form of ethyl 3-[2-chloro- 4-fluoro-5-[3-methyl-2,6-dioxo-4-(trifluoromethyl)pyrimidin-1 -yl]phenyl]-5-methyl-4H-isoxazole-5- carboxylate, designated Form 1 , wherein the polymorph is characterized by a powder X-ray diffraction pattern expressed in terms of 20 angles, wherein the powder X-ray diffraction pattern comprises: a) at least one 20 angle value at 6.5 ± 0.2, b) at least one 20 angle value at 7.2 ± 0.2, c) at least one 20 angle value at 7.4 ± 0.2, and d) at least one, preferably two, more preferably three, yet more preferably more than four 20 angle values selected from the group comprising: 8.9 ± 0.2, 12.9 ± 0.2, 14.3 ± 0.2, 14.8 ± 0.2, 16.1 ± 0.2, 17.3 ± 0.2, 19.4 ± 0.2, 20.5 ± 0.2, 23.5 ± 0.2, 25.0 ± 0.2, 26.2 ± 0.2, 28.2 ± 0.2, and 29.4 ± 0.2 (see Fig. 1 ).

[0011] Preferably, the powder X-ray diffraction pattern for polymorph designated Form 1 comprises: a) at least one 20 angle value at 6.5 ± 0.2, b) at least one 20 angle value at 7.2 ± 0.2, c) at least one 20 angle value at 7.4 ± 0.2, d) at least one 20 angle value at 12.9 ± 0.2, and e) at least one, preferably two, more preferably three, yet more preferably more than four 20 angle values selected from the group comprising: 8.9 ± 0.2, 14.3 ± 0.2, 14.8 ± 0.2, 16.1 ± 0.2, 17.3 ± 0.2, 19.4 ± 0.2, 20.5 ± 0.2, 23.5 ± 0.2, 25.0 ± 0.2, 26.2 ± 0.2, 28.2 ± 0.2, and 29.4 ± 0.2.

[0012] More preferably, the powder X-ray diffraction pattern for polymorph designated Form 1 comprises: a) at least one 20 angle value at 6.5 ± 0.2, b) at least one 20 angle value at 7.2 ± 0.2, c) at least one 20 angle value at 7.4 ± 0.2, d) at least one 20 angle value at 12.9 ± 0.2, e) at least one 20 angle value at 17.3 ± 0.2, and f) at least one, preferably two, more preferably three, yet more preferably more than four 20 angle values selected from the group comprising: 8.9 ± 0.2, 14.3 ± 0.2, 14.8 ± 0.2, 16.1 ± 0.2, 19.4 ± 0.2, 20.5 ± 0.2, 23.5 ± 0.2, 25.0 ± 0.2, 26.2 ± 0.2, 28.2 ± 0.2, and 29.4 ± 0.2.

[0013] Even more preferably, the powder X-ray diffraction pattern for polymorph designated Form 1 comprises: a) at least one 20 angle value at 6.5 ± 0.2, b) at least one 20 angle value at 7.2 ± 0.2, c) at least one 20 angle value at 7.4 ± 0.2, d) at least one 20 angle value at 12.9 ± 0.2, e) at least one 20 angle value at 17.3 ± 0.2, f) at least one 20 angle value at 19.4 ± 0.2, and g) at least one, preferably two, more preferably three, yet more preferably more than four 20 angle values selected from the group comprising: 8.9 ± 0.2, 14.3 ± 0.2, 14.8 ± 0.2, 16.1 ± 0.2, 20.5 ± 0.2, 23.5 ± 0.2, 25.0 ± 0.2, 26.2 ± 0.2, 28.2 ± 0.2, and 29.4 ± 0.2.

[0014] In another embodiment of the invention, the crystalline polymorph designated Form 1 of the compound of formula (I) is characterized by the unit cell parameters of its single crystal as shown in Table 1 . The polymorph was obtained using the method of Example 1 a.

[0015] TABLE 1

[0016] In the table, a, b, c = Length of the edges of the unit cell; a, p , y = Angles of the unit cell.

[0017] Thus, in one embodiment of the present invention, the crystalline polymorph of the invention designated Form 1 has the following lattice parameters: a = 55.3 A ± 0.5 A, b = 9.4 A ± 0.5 A, c = 24.9 A ± 0.5 A, a = 90° ± 0.1 °, p = 98.6° ± 0.1 °, y = 90° ± 0.1 °, and volume = 12728 A3± 127 A3.

[0018] Furthermore, in one embodiment, the crystalline polymorph of the invention designated Form 1 has a melting point of 81 °C ± 5°C, preferably a melting point of 81 °C ± 2°C, as obtained using Differential Scanning Calorimetry (DSC) with a heating rate of 10°C / minute (see Fig. 2).

[0019] In a further aspect, the present invention provides crystalline polymorph designated Form 1 having an infrared absorption spectrum with at least two, preferably three, four, five, six, seven, eight, nine or more absorption peaks at 2980 cm- 1, 2891 cm- 1, 1728 cm- 1, 1676 cm- 1, 1612 cm- 1, 1490 cm- 1, 1418 nr1, 1372 cm'1, 1333 cm- 1, 1269 cm- 1, 1 179 cm- 1, 1 147 cm- 1, 1044 cm- 1, 970 cm- 1, 928 cm- 1, 902 cm- 1, 858 cm- 1, 826 cm- 1, 756 cm- 1, 728 cm- 1, 686 cm- 1, 655 cm- 1, 615 cm- 1, and 588 cm- 1(see Fig. 3).

[0020] According to a second aspect, there is provided a novel crystalline form of ethyl 3-[2-chloro-4-fluoro-5- [3-methyl-2,6-dioxo-4-(trifluoromethyl)pyrimidin-1 -yl]phenyl]-5-methyl-4H-isoxazole-5-carboxylate, designated Form 2, wherein the polymorph is characterized by a powder X-ray diffraction pattern expressed in terms of 20 angles, wherein the powder X-ray diffraction pattern comprises: a) at least one 20 angle value at 6.1 ± 0.2, b) at least one 20 angle value at 7.0 ± 0.2, and c) at least one, preferably two, more preferably three 20 angle values selected from the group comprising 10.9 ± 0.2, 12.3 ± 0.2, 13.5 ± 0.2, 14.1 ± 0.2, 14.7 ± 0.2, 15.3 ± 0.2, 15.9 ± 0.2, 16.9 ± 0.2, 17.1 ± 0.2, 19.4 ± 0.2, 19.7 ± 0.2, 20.1 ± 0.2, 20.4 ± 0.2, 20.8 ± 0.2, 21 .4 ± 0.2, 23.4 ± 0.2, 24.1 ± 0.2, 25.0 ± 0.2, and 26.0 ± 0.2 (see Fig. 5).

[0021] The novel crystalline form of ethyl 3-[2-chloro-4-fluoro-5-[3-methyl-2,6-dioxo-4- (trif I uoromethy l)py ri m idi n- 1 -yl]phenyl]-5-methyl-4H-isoxazole-5-carboxylate, designated Form 2, wherein the polymorph is characterized by a powder X-ray diffraction pattern expressed in terms of 20 angles, wherein the powder X-ray diffraction pattern comprises: d) at least one 20 angle value at 6.1 ± 0.2, e) at least one 20 angle value at 7.0 ± 0.2, and f) at least one, preferably two, more preferably three 20 angle values selected from the group comprising 10.9 ± 0.2, 12.3 ± 0.2, 13.5 ± 0.2, 14.1 ± 0.2, 14.7 ± 0.2, 15.3 ± 0.2, 15.9 ± 0.2, 16.9 ± 0.2, 17.1 ± 0.2, 19.4 ± 0.2, 19.7 ± 0.2, 20.1 ± 0.2, 20.4 ± 0.2, 20.8 ± 0.2, 21 .4 ± 0.2, 23.4 ± 0.2, 24.1 ± 0.2, 25.0 ± 0.2, and 26.0 ± 0.2 (see Fig. 5), is characterized in that it is prepared by the following steps: i. Adding a mixture of methylcyclohexane and toluene to the compound of formula (I); ii. Heating and stirring the resulting mixture until the solids of the compound of formula (I) are dissolved;

[0022] Hi. Cooling the mixture gradually such that an oil phase is formed; and iv. Stirring the resulting oil phase until a crystalline polymorph is formed.

[0023] Preferably, the powder X-ray diffraction pattern for polymorph designated Form 2 comprises: a) at least one 20 angle value at 6.1 ± 0.1 , b) at least one 20 angle value at 7.0 ± 0.1 , and c) at least one, preferably two, more preferably three 20 angle values selected from the group comprising 10.9 ± 0.1 , 12.3 ± 0.1 , 13.5 ± 0.1 , 14.1 ± 0.1 , 14.7 ± 0.1 , 15.3 ± 0.1 , 15.9 ± 0.1 ,

[0024] 16.9 ± 0.1 , 17.1 ± 0.1 , 19.4 ± 0.1 , 19.7 ± 0.1 , 20.1 ± 0.1 , 20.4 ± 0.1 , 20.8 ± 0.1 , 21 .4 ± 0.1 ,

[0025] 23.4 ± 0.1 , 24.1 ± 0.1 , 25.0 ± 0.1 , and 26.0 ± 0.1 .

[0026] Furthermore, in an embodiment, the crystalline polymorph designated Form 2 has a powder X-ray diffraction pattern comprising one 20 angle value at 6.1 ± 0.2, at least one 20 angle value at 7.0 ± 0.2, and at least four, preferably five, more preferably six, yet more preferably seven, again more preferably eight, nine, ten, eleven, twelve, thirteen, fourteen, fifteen or most preferably all 20 angle values selected from the group comprising 10.9 ± 0.2, 12.3 ± 0.2, 13.5 ± 0.2, 14.1 ± 0.2, 14.7 ± 0.2, 15.3 ± 0.2, 15.9 ± 0.2, 16.9 ± 0.2, 17.1 ± 0.2, 19.4 ± 0.2, 19.7 ± 0.2, 20.1 ± 0.2, 20.4 ± 0.2, 20.8 ± 0.2, 21 .4 ± 0.2, 23.4 ± 0.2, 24.1 ± 0.2, 25.0 ± 0.2, and 26.0 ± 0.2.

[0027] In another embodiment, the crystalline polymorph designated Form 2 of the compound of formula (I) is characterized by the unit cell parameters of its single crystal as shown in Table 2. The polymorph was obtained using the method of Example 1 b.

[0028] TABLE 2

[0029] In the table, a, b, c = Length of the edges of the unit cell; a, p , y = Angles of the unit cell.

[0030] Thus, in one embodiment, the crystalline Form 2 polymorph has the following lattice parameters: a = 57.7 A ± 0.5 A, b = 9.5 A ± 0.5 A, c = 24.9 A ± 0.5 A, a = 90° ± 0.1 °, p = 96.0° ± 0.5°, y = 90° ± 0.1 °, and volume = 13532 A3± 135 A3.

[0031] There is provided a crystalline polymorph of the compound of formula (I) designated Form 2, which has the following lattice parameters: a = 57.7 A ± 0.5 A, b = 9.5 A ± 0.5 A, c = 24.9 A ± 0.5 A, a = 90° ± 0.1 °, p = 96.0° ± 0.5°, y = 90° ± 0.1 °, and volume = 13532 A3± 135 A3, and is characterized in that it is prepared by the following steps: i) Adding a mixture of methylcyclohexane and toluene to the compound of formula (I); ii) Heating and stirring the resulting mixture until the solids of the compound of formula (I) are dissolved;

[0032] Hi) Cooling the mixture gradually such that an oil phase is formed; and iv) Stirring the resulting oil phase until a crystalline polymorph is formed.

[0033] Furthermore, in one embodiment, the crystalline polymorph designated Form 2 has a melting point of 70°C ± 5°C, preferably a melting point of 70°C ± 2°C, as obtained using Differential Scanning Calorimetry (DSC) with a heating rate of 10°C / minute (see Fig. 6).

[0034] In a further embodiment, there is provided crystalline polymorph designated Form 2, having an infrared absorption spectrum with at least two, preferably three, four, five, six, seven, eight, nine or more absorption peaks at 3122 cm- 1, 3076 cm- 1, 2986 cm- 1, 2936 cm- 1, 1728 cm- 1, 1673 cm- 1, 1612 cm- 1, 1579 cm1, 1492 cm1, 1424 nr1, 1409 cm1, 1371 cm1, 1333 cm1, 1306 cm1, 1270 cm1, 1248 cm-1, 1225 cm- 1, 1 179 cm- 1, 1 146 cm- 1, 1 1 12 cm- 1, 1085 cm- 1, 1044 cm- 1, 1022 cm- 1, 970 cm- 1, 928 cm-1, 916 cm- 1, 900 cm- 1, 858 cm- 1, 826 cm- 1, 756 cm- 1, 729 cm- 1, 708 cm- 1, 686 cm- 1, 654 cm- 1, 615 cnr1, 587 cm1, and 543 cm1(see Fig. 7).

[0035] The present invention also relates to methods for the preparation of the polymorphs of the invention directly from solution.

[0036] Thus, in one aspect of the invention, there is provided a method for preparing a crystalline polymorph of the compound of formula (I) designated Form 1 , comprising: i) Adding a mixture of ethanol and water to the compound of formula (I); ii) Heating and stirring the resulting mixture until the solids of the compound of formula (I) are dissolved;

[0037] Hi) Cooling the mixture gradually such that an oil phase is formed; and iv) Leaving the resulting oil phase undisturbed until a crystalline polymorph is formed.

[0038] Preferably, the mixture of ethanol and water in step i) is present at a ratio of 90:10 vol / vol%.

[0039] Preferably, the resulting mixture of step i) is present as a 15 % to 25 % solution by weight / volume (w / v). More preferably, the resulting mixture of step i) is present as a 18 % to 22 % solution by weight / vol. Even more preferably, the resulting mixture of step i) is present as a 20 % solution by weight / vol.

[0040] Preferably, in step ii), the mixture is heated to 40 °C to 60 °C. More preferably, the mixture is heated to 45 °C to 55 °C. Even more preferably, the mixture is heated to 48 °C to 52 °C. More preferably still, the mixture is heated to 50 °C.

[0041] Preferably, in step iii), the mixture is cooled gradually to -5 °C to -15 °C. More preferably, the mixture is cooled gradually to -8 °C to -12 °C. Even more preferably, the mixture is cooled gradually to -10 °C.

[0042] Preferably, in step iii), once the mixture has cooled, it is held at the resulting temperature for at least 12 hours.

[0043] In another aspect, the present invention provides a crystalline polymorph of the compound of formula (I) designated Form 1 , obtainable by the above process.

[0044] In another aspect, there is provided a method for preparing a crystalline polymorph of the compound of formula (I) designated Form 2, comprising: v) Adding a mixture of methylcyclohexane and toluene to the compound of formula (I); vi) Heating and stirring the resulting mixture until the solids of the compound of formula (I) are dissolved; vii) Cooling the mixture gradually such that an oil phase is formed; and viii) Stirring the resulting oil phase until a crystalline polymorph is formed.

[0045] Preferably, the mixture of methylcyclohexane and toluene in step i) is present at a ratio of 70:30 vol / vol.

[0046] Preferably, the resulting mixture of step i) is present as a 15 % to 25 % solution by weight / volume. More preferably, the resulting mixture of step i) is present as a 18 % to 22 % solution by weight / volume. Even more preferably, the resulting mixture of step i) is present as a 20 % solution by weight / volume.

[0047] Preferably, in step ii), the mixture is heated to 60 °C to 80 °C. More preferably, the mixture is heated to 65 °C to 75 °C. Even more preferably, the mixture is heated to 68 °C to 75 °C. More preferably still, the mixture is heated to 70 °C. Preferably, in step iii), the mixture is cooled gradually to -5 °C to -15 °C. More preferably, the mixture is cooled gradually to -8 °C to -12 °C. Even more preferably, the mixture is cooled gradually to -10 °C.

[0048] Preferably, in step iii), once the mixture has cooled, it is held at the resulting temperature for at least 12 hours.

[0049] In another embodiment, the present invention provides a crystalline polymorph of the compound of formula (I) designated Form 2, obtainable by the above process.

[0050] The compound of formula (I) may occur in two isomeric forms, (la) and (lb):

[0051] The present invention is intended to cover polymorphic forms of both isomers (la) and (lb), as well as mixtures of these isomers and also enantioenriched forms of the compound of formula (I).

[0052] The polymorphs of the invention may be readily incorporated into herbicidal compositions by conventional means. Accordingly, in a further aspect, the invention provides an herbicidal composition comprising a polymorph of the invention as defined above and an agriculturally acceptable carrier or diluent.

[0053] In one embodiment, the composition of the invention comprises i) a crystalline polymorph of the compound of formula (I) designated Form 1 , ii) a crystalline polymorph of the compound of formula (I) designated Form 2, or iii) a mixture thereof.

[0054] In another embodiment, the present invention also relates to a composition comprising at least one polymorph according to the invention and an amorphous form of the compound of formula (I).

[0055] Preferably, the compound of formula (I) present in the agricultural composition comprises at least 70 mol% of a polymorph of the present invention, more preferably 80 mol% of a polymorph of the present invention, more preferably still at least 90 mol% of a polymorph of the present invention.

[0056] In particular, use of a specific polymorph may allow use of new formulations compared with existing polymorphic / amorphous forms of a compound. This might be advantageous for a number of reasons. For example, a suspension concentrate (SC) formulation may be preferred over an emulsion concentrate (EC) because the lack of solvent in the SC often means that the formulation is likely to be less phytotoxic than an equivalent EC formulation - however, if the existing form of a compound is not stable in such an SC formulation, polymorphic conversion might occur leading to unwanted crystal growth. Such crystal growth is detrimental because it leads to, for example, thickening and potentially solidification of the formulation which can lead to blockages in application equipment, e.g. in spray nozzles in agricultural application machinery. Using a stable polymorphic form would overcome these issues.

[0057] The agrochemical compositions comprising a polymorph of the present invention may be applied as a suspension concentrate (SC), oil dispersion (OD), wettable powder (WP), water dispersible granule (WG), a suspoemulsion (SE) formulation, or a mixture of a capsule suspension and suspension concentrate (ZC) formulation. Preferably, the agrochemical compositions comprising a polymorph of the present invention are applied as a SC or a WG formulation. More preferably, the agricultural composition is a SC formulation. Use of the crystalline form provides multiple surprising advantages over the amorphous form in a SC formulation. For example, use of the crystalline form in a SC formulation means easier milling and significantly higher final active ingredient concentration. Furthermore, use of the crystalline form in a SC formulation also resulted in lower particle size and better dispersion.

[0058] In another aspect, the present invention also relates to an agricultural composition comprising a polymorph according to the invention, and at least one agriculturally acceptable carrier or diluent.

[0059] Preferably, the composition may comprise at least one further active ingredient, such as a pesticide, for instance one or more acaricides, bactericides, fungicides, herbicides, insecticides, nematicides, as well as plant nutrients and plant fertilizers.

[0060] Preferably, the agricultural composition comprising a polymorph according to the invention, and at least one herbicide. More preferably, the at least one further pesticide is at least one herbicide selected from S-metolachlor, glufosinate, L-glufosinate, glyphosate, mesotrione, bicyclopyrone, metribuzin, trifludimoxazin, saflufenacil, fomesafen, pyroxasulfone, ALS- and ACCase inhibitors and synthetic Auxins. Most preferably, the at least one further pesticide is at least one herbicide selected from S- metolachlor, glufosinate, L-glufosinate, glyphosate, mesotrione, bicyclopyrone, metribuzin, trifludimoxazin and saflufenacil.

[0061] In another embodiment, the present invention also relates to 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 polymorph, or a composition comprising the polymorph according to the invention.

[0062] In another embodiment, the present invention also relates to 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 composition comprising a polymorph according to the invention.

[0063] In another embodiment, the present invention also relates to use of a polymorph according to the invention over crops that are resistant to the compound of formula (I). Crops may have been rendered resistant to the compound of formula (I) by conventional methods of breeding or by genetic engineering. In another embodiment, the present invention also relates to use of a polymorph according to the invention for controlling the growth of protoporphyrinogen IX oxidase (PPO) inhibitor herbicide resistant weeds, such as flumioxazin, fomesafen, and / or lactofen. The weeds may have been rendered tolerant to PPO herbicides by evolution, by conventional methods of breeding or by genetic engineering. Examples of weeds that have developed resistance to PPO herbicides include Amaranthus spp.. In particular, weeds that have developed resistance to PPO herbicides include Amaranthus palmeri, Amaranthus retroflexus, and Amaranthus tuberculatus.

[0064] In particular, there is provided the use of a polymorph according to the invention for controlling the growth of protoporphyrinogen IX oxidase (PPO) inhibitor herbicide resistant weeds, wherein the protoporphyrinogen IX oxidase (PPO) inhibitor herbicide resistant weeds have a mutation at amino acid 128, amino acid 210, and / or amino acid 399 in the gene coding for the protoporphyrinogen oxidase enzyme. Preferably, there is provided the use of a polymorph according to the invention for controlling the growth of protoporphyrinogen IX oxidase (PPO) inhibitor herbicide resistant weeds, wherein the protoporphyrinogen IX oxidase (PPO) inhibitor herbicide resistant weeds have a mutation at amino acid 128 and / or amino acid 210 in the gene coding for the protoporphyrinogen oxidase enzyme.

[0065] 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. Contrarily, 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 herbicide , 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, hygroscopicity, suspensibility, dissolution rate, biological availability and efficacy. 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, the ease with which a compound can be combined in a formulation with other active ingredients and formulation components and the quality and efficacy of plant treatment agents, such as herbicides. 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.

[0066] Amorphous forms can also lead to difficulties in handling and weighing the active ingredient in its solid form. When stored above its glass transition temperature, the material can form a sticky gum or glassy solid over time, which adheres to the walls of containers and is difficult to transfer to other vessels without significant material losses. A stable polymorphic form may be stored at higher temperatures and remain as a free-flowing solid, which is easier to transfer between vessels without unreasonable material losses.

[0067] 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. Single crystal diffraction, such as x-ray or electron or neutrons diffraction, is especially useful in identifying crystal structures.

[0068] The polymorphs of the invention may be applied in unchanged form but is more preferably incorporated into agrochemical compositions by conventional means. Accordingly, in a further aspect, the invention provides an agrochemical composition comprising the polymorphs of the invention as defined above and at least one agriculturally acceptable carrier or diluent.

[0069] The agrochemical compositions comprising the polymorphs of the present invention are preventively and / or curatively valuable active ingredients in the field of pest control, even at low rates of application, have a favourable biocidal spectrum and are well tolerated by warm-blooded species, fish and plants.

[0070] Crops of useful plants in which the compositions according to the invention can be used include perennial and annual crops, such as berry plants for example blackberries, blueberries, cranberries, raspberries and strawberries; cereals for example barley, maize (corn), millet, oats, rice, rye, sorghum triticale and wheat; fibre plants for example cotton, flax, hemp, jute and sisal; field crops for example sugar and fodder beet, coffee, hops, mustard, oilseed rape (canola), poppy, sugar cane, sunflower, tea and tobacco; fruit trees for example apple, apricot, avocado, banana, cherry, citrus, nectarine, peach, pear and plum; grasses for example Bermuda grass, bluegrass, bentgrass, centipede grass, fescue, ryegrass, St. Augustine grass and Zoysia grass; herbs such as basil, borage, chives, coriander, lavender, lovage, mint, oregano, parsley, rosemary, sage and thyme; legumes for example beans, lentils, peas and soya beans; nuts for example almond, cashew, ground nut, hazelnut, peanut, pecan, pistachio and walnut; palms for example oil palm; ornamentals for example flowers, shrubs and trees; other trees, for example cacao, coconut, olive and rubber; vegetables for example asparagus, aubergine, broccoli, cabbage, carrot, cucumber, garlic, lettuce, marrow, melon, okra, onion, pepper, potato, pumpkin, rhubarb, spinach and tomato; and vines for example grapes. Preferred crop plants include maize, wheat, barley and rice.

[0071] Crops are to be understood as being those which are naturally occurring, obtained by conventional methods of breeding, or obtained by genetic engineering. They include crops which contain so-called output traits (e.g. improved storage stability, higher nutritional value and improved flavour).

[0072] Crops are to be understood as also including those crops which have been rendered tolerant to herbicides like bromoxynil or classes of herbicides such as ALS-, EPSPS-, GS-, HPPD- and PPO- inhibitors. An example of a crop that has been rendered tolerant to imidazolinones, e.g. imazamox, by conventional methods of breeding is Clearfield® summer canola. Examples of crops 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®, Herculex I® and LibertyLink®.

[0073] Crops are also to be understood as being those which naturally are or have been rendered resistant to harmful insects. This includes plants transformed by the use of recombinant DNA techniques, for example, to be capable of synthesizing one or more selectively acting toxins, such as are known, for example, from toxin-producing bacteria. Examples of toxins which can be expressed include 5- endotoxins, vegetative insecticidal proteins (Vip), insecticidal proteins of bacteria colonizing nematodes, and toxins produced by scorpions, arachnids, wasps and fungi.

[0074] An example of a crop that has been modified to express the Bacillus thuringiensis toxin is the Bt maize KnockOut® (Syngenta Seeds). An example of a crop comprising more than one gene that codes for insecticidal resistance and thus expresses more than one toxin is VipCot® (Syngenta Seeds). Crops or seed material thereof can also be resistant to multiple types of pests (so-called stacked transgenic events when created by genetic modification). For example, a plant can have the ability to express an insecticidal protein while at the same time being herbicide tolerant, for example Herculex I® (Dow AgroSciences, Pioneer Hi-Bred International).

[0075] The rate at which the agrochemical compositions of the invention are applied will depend upon the particular type of weed etc. to be controlled, the degree of control required and the timing and method of application and can be readily determined by the person skilled in the art. In general, the compositions of the invention can be applied at an application rate of between 0.005 kilograms / hectare (kg / ha) and about 5.0kg / ha, based on the total amount of active ingredient (wherein 'active ingredient' means the polymorph of the invention) in the composition. An application rate of between about 0.01 kg / ha and about 0.2kg / ha is preferred, with an application rate of between about 0.03kg / ha and 0.1 kg / ha being especially preferred.

[0076] In practice, the agrochemical compositions comprising the polymorphs of the invention are applied as a formulation containing the various co-formulants, adjuvants and carriers known to or used in the industry.

[0077] These formulations can be in various physical forms, e.g. in the form of dusting powders, gels, wettable powders, water-dispersible granules, water-dispersible tablets, effervescent pellets, emulsifiable concentrates, microemulsifiable concentrates, oil-in-water emulsions, oil-flowables, aqueous dispersions, oily dispersions, suspo-emulsions, suspension concentrates, capsule suspensions, emulsifiable granules, soluble liquids, water-soluble concentrates (with water or a water-miscible organic solvent as carrier), impregnated polymer films or in other forms known e.g. from the Manual on Development and Use of FAO and WHO Specifications for Pesticides, United Nations, First Edition, Second Revision (2010). Such formulations can either be used directly or diluted prior to use. The dilutions can be made, for example, with water, liquid fertilisers, micronutrients, biological organisms, oil or solvents.

[0078] The formulations can be prepared e.g. by mixing a polymorph ('active ingredient') with the co-formulants in order to obtain formulations in the form of finely divided solids, granules, solutions, dispersions or emulsions. The active ingredient can also be formulated with other co-formulants, 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.

[0079] The active ingredient can also be contained in very fine microcapsules. Microcapsules contain the active ingredient in a porous carrier. This enables the active ingredient to be released into the environment in controlled amounts (e.g. slow-release). Microcapsules usually have a diameter of from 0.1 to 500 microns. They contain the active ingredient in an amount of about from 25 to 95 % by weight of the capsule weight. The active ingredient can be in the form of a monolithic solid, in the form of fine particles in solid or liquid dispersion or in the form of a suitable solution. The encapsulating membranes can 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 polymers that are known to the person skilled in the art. 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.

[0080] The formulation co-formulants that are suitable for the preparation of the formulations 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, 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, A / ,A / -dimethylformamide, dimethyl sulfoxide, 1 ,4- dioxane, dipropylene glycol, dipropylene glycol methyl ether, dipropylene glycol dibenzoate, diproxitol, alkylpyrrolidone, ethyl acetate, 2-ethylhexanol, ethylene carbonate, 1 ,1 ,1 -trichloroethane, 2-heptanone, alpha-pinene, d-limonene, ethyl lactate, ethylene glycol, ethylene glycol butyl ether, ethylene glycol methyl ether, gamma-butyrolactone, glycerol, glycerol acetate, glycerol diacetate, glycerol triacetate, hexadecane, hexylene glycol, isoamyl acetate, 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, A / ,A / -dimethylamides based on fatty acids, octadecanoic acid, octylamine acetate, oleic acid, oleylamine, o-xylene, phenol, polyethylene glycol, propionic acid, propyl lactate, propylene carbonate, propylene glycol, propylene glycol methyl ether, p-xylene, toluene, triethyl phosphate, triethylene glycol, xylenesulfonic acid, paraffin, mineral oil, trichloroethylene, perchloroethylene, ethyl acetate, amyl acetate, butyl acetate, propylene glycol methyl ether, diethylene glycol methyl ether, methanol, ethanol, isopropanol, and alcohols of higher molecular weight, such as amyl alcohol, tetrahydrofurfuryl alcohol, hexanol, octanol, ethylene glycol, propylene glycol, glycerol, N- methyl-2-pyrrolidone and the like.

[0081] 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.

[0082] A large number of surface-active substances can advantageously be used in both solid and liquid formulations, especially in those formulations which can be diluted with a carrier prior to use. Surfaceactive 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 dialkylphosphate esters; and also further substances described e.g. in McCutcheon's Detergents and Emulsifiers Annual, MC Publishing Corp., Ridgewood New Jersey (1981 ).

[0083] Further co-formulants that can be used in pesticidal 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 liquid and solid fertilisers. The formulations according to the invention can 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 formulations according to the invention is generally from 0.01 to 10 %, based on the mixture to be applied. For example, the oil additive can be added to a spray tank in the desired concentration after a 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, 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. Preferred oil additives comprise alkyl esters of C8-C22 fatty acids, especially the methyl derivatives of C12-C18 fatty acids, for example the methyl esters of lauric acid, palmitic acid and oleic acid (methyl laurate, methyl palmitate and methyl oleate, respectively). Many oil derivatives are known from the Compendium of Herbicide Adjuvants, 10th Edition, Southern Illinois University, 2010.

[0084] The inventive formulations generally comprise from 0.1 to 99 % by weight, especially from 0.1 to 95 % by weight, of polymorphs of the present invention and from 1 to 99.9 % by weight of a co-formulant which preferably includes from 0 to 25 % by weight of a surface-active substance. Whereas commercial products may preferably be formulated as concentrates, the end user will normally employ dilute formulations.

[0085] The rates of application vary within wide limits and depend on the nature of the soil, the method of application, the crop plant, the pest to be controlled, the prevailing climatic conditions, and other factors governed by the method of application, the time of application and the target crop. As a general guideline, compounds may be applied at a rate of from 1 to 2000 g / ha, especially from 10 to 1000 g / ha.

[0086] Preferred formulations can have the following compositions (weight %):

[0087] Emulsifiable concentrates: active ingredient: 1 to 95 %, preferably 10 to 40 % surface-active agent: 1 to 30 %, preferably 5 to 20 % liquid carrier: 1 to 80 %, preferably 1 to 60 %

[0088] Dusts: active ingredient: 0.1 to 10 %, preferably 0.1 to 5 % solid carrier: 99.9 to 90 %, preferably 99.9 to 99 %

[0089] Suspension concentrates: active ingredient: 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 %

[0090] Wettable powders: active ingredient: 0.5 to 90 %, preferably 1 to 80 % surface-active agent: 0.5 to 20 %, preferably 1 to 15 % solid carrier: 5 to 95 %, preferably 15 to 90 %

[0091] Granules: active ingredient: 0.1 to 90 %, preferably 40 to 80 % solid carrier: 99.5 to 5 %, preferably 97 to 15 %

[0092] The following Examples further illustrate, but do not limit, the invention. Wettable powders a) b) c) active ingredient 25 % 50% 75 % sodium lignosulfonate 5 % 5 % sodium lauryl sulfate 3 % - 5% sodium

[0093] 6% 10 % diisobutylnaphthalenesulfonate phenol polyethylene glycol ether 2 % (7-8 mol of ethylene oxide) highly dispersed silicic acid 5% 10 % 10 % Kaolin 62% 27%

[0094] The combination is thoroughly mixed with the adjuvants and the mixture is thoroughly ground in a suitable mill, affording wettable powders that can be diluted with water to give suspensions of the desired concentration.

[0095] Powders for dry seed treatment a) b) active ingredient 25 % 50% 75 % light mineral oil 5 % 5% 5% highly dispersed silicic acid 5 % 5 %

[0096] Kaolin 65 % 40 %

[0097] Talcum 20

[0098] The combination is thoroughly mixed with the adjuvants and the mixture is thoroughly ground in a suitable mill, affording powders that can be used directly for seed treatment.

[0099] Emulsifiable concentrate active ingredient 10 % octylphenol polyethylene glycol ether 3 %

[0100] (4-5 mol of ethylene oxide) calcium dodecylbenzenesulfonate 3 % castor oil polyglycol ether (35 mol of ethylene oxide) 4%

[0101] Cyclohexanone 30% xylene mixture 50% Emulsions of any required dilution, which can be used in plant protection, can be obtained from this concentrate by dilution with water.

[0102] Dusts a) b) c) active ingredient 5 % 6% 4%

[0103] Talcum 95 %

[0104] Kaolin 94% mineral filler 96 %

[0105] Ready-for-use dusts are obtained by mixing the combination with the carrier and grinding the mixture in a suitable mill. Such powders can also be used for dry dressings for seed. Extruder granules active ingredient 15 % sodium lignosulfonate 2 % carboxymethylcellulose 1 %

[0106] Kaolin 82 %

[0107] The combination 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.

[0108] Coated granules active ingredient 8% polyethylene glycol (mol. wt. 200) 3%

[0109] Kaolin 89%

[0110] The finely ground combination is uniformly applied, in a mixer, to the kaolin moistened with polyethylene glycol. Non-dusty coated granules are obtained in this manner. Suspension concentrate active ingredient 40 % propylene glycol 10 % nonylphenol polyethylene glycol ether

[0111] (15 mol of ethylene oxide)

[0112] Sodium lignosulfonate 10 % carboxymethylcellulose 1 % silicone oil (in the form of a 75 % emulsion in water) °

[0113] Water 32%

[0114] The finely ground combination is intimately mixed with the adjuvants, giving a suspension concentrate from which suspensions of any desired dilution can be obtained by dilution with water. Using such dilutions, living plants as well as plant propagation material can be treated and protected against infestation by microorganisms, by spraying, pouring or immersion.

[0115] Flowable concentrate for seed treatment active ingredient 40 % propylene glycol 5 % copolymer butanol PO / EO 2%

[0116] Tristyrenephenole with 10-20 moles EO 2%

[0117] 1 ,2-benzisothiazolin-3-one (in the form of a 20% solutionn c, . U.O 70 in water) monoazo-pigment calcium salt 5 %

[0118] Silicone oil (in the form of a 75 % emulsion in water) 0.2 % Water 45.3 %

[0119] The finely ground combination is intimately mixed with the adjuvants, giving a suspension concentrate from which suspensions of any desired dilution can be obtained by dilution with water. Using such dilutions, living plants as well as plant propagation material can be treated and protected against infestation by microorganisms, by spraying, pouring or immersion.

[0120] Slow Release

[0121] 28 parts of the active ingredient are mixed with 2 parts of an aromatic solvent and 7 parts of toluene diisocyanate / polymethylene-polyphenylisocyanate-mixture (8:1 ). This mixture is emulsified in a mixture of 1 .2 parts of polyvinylalcohol, 0.05 parts of a defoamer and 51 .6 parts of water until the desired particle size is achieved. To this emulsion a mixture of 2.8 parts 1 ,6-diaminohexane in 5.3 parts of water is added. The mixture is agitated until the polymerization reaction is completed. The obtained capsule suspension is stabilized by adding 0.25 parts of a thickener and 3 parts of a dispersing agent. The capsule suspension formulation contains 28% of the active ingredient. The medium capsule diameter is 8-15 microns. The resulting formulation is applied to seeds as an aqueous suspension in an apparatus suitable for that purpose.

[0122] Each of the above formulations can be prepared as a package containing the polymorph of the invention together with other ingredients of the formulation (diluents, emulsifiers, surfactants, etc.). The formulations can also be prepared by a tank mix method, in which the ingredients are obtained separately and combined at the grower site.

[0123] These formulations can be applied to the areas where control is desired by conventional methods. Dust and liquid formulations, for example, can be applied by the use of power-dusters, broom and hand sprayers and spray dusters. The formulations can also be applied from airplanes as a dust or a spray or by rope wick applications. Both solid and liquid formulations may also be applied to the soil in the locus of the plant to be treated allowing the active ingredient to penetrate the plant through the roots. The formulations of the invention may also be used for dressing applications on plant propagation material to provide protection against insect infections on the plant propagation material as well as against insects occurring in the soil. Suitably, the active ingredient may be applied to plant propagation material to be protected by impregnating the plant propagation material, in particular, seeds, either with a liquid formulation of the polymorph or coating it with a solid formulation. In special cases, other types of application are also possible, for example, the specific treatment of plant cuttings or twigs serving propagation.

[0124] Normally, in the management of a crop a grower would use one or more other agronomic chemicals in addition to the crystalline polymorph of the present invention. Examples of agronomic chemicals include pesticides, such as acaricides, bactericides, fungicides, herbicides, insecticides, nematicides, as well as plant nutrients and plant fertilizers. The crystalline polymorph of the present invention can also be used in mixture with one or more additional herbicides and / or plant growth regulators. Examples of such additional herbicides or plant growth regulators include acetochlor, acifluorfen (including acifluorfen-sodium), aclonifen, ametryn, amicarbazone, aminopyralid, aminotriazole, atrazine, beflubutamid-M, benquitrione, bensulfuron (including bensulfuron-methyl), bentazone, bicyclopyrone, bilanafos, bipyrazone, bispyribac -sodium, bixlozone, broclozone, bromacil, bromoxynil, butachlor, butafenacil, carfentrazone (including carfentrazone-ethyl), cloransulam (including cloransulam-methyl), chlorimuron (including chlorimuron- ethyl), chlorotoluron, chlorsulfuron, cinmethylin, clacyfos, clethodim, clodinafop (including clodinafop- propargyl), clomazone, clopyralid, cyclopyranil, cyclopyrimorate, cyclosulfamuron, cyhalofop (including cyhalofop-butyl), 2,4-D (including the choline salt and 2-ethylhexyl ester thereof), 2,4-DB, desmedipham, dicamba (including the aluminium, aminopropyl, bis-aminopropylmethyl, choline, dichloroprop, diglycolamine, dimethylamine, dimethylammonium, potassium and sodium salts thereof) diclosulam, diflufenican, diflufenzopyr, dimethachlor, dimethenamid-P, dioxopyritrione, diquat dibromide, diuron, epyrifenacil, ethalfluralin, ethofumesate, fenoxaprop (including fenoxaprop-P-ethyl), fenoxasulfone, fenpyrazone, fenquinotrione, fentrazamide, flazasulfuron, florasulam, florpyrauxifen (including florpyrauxifen-benzyl), fluazifop (including fluazifop-P-butyl), flucarbazone (including flucarbazone- sodium), fluchloraminopyr (including fluchloramino-tefuryl), flufenacet, flufenoximacil, flumetsulam, flumioxazin, fluometuron, fomesafen flupyrsulfuron (including flupyrsulfuron-methyl-sodium), fluroxypyr (including fluroxypyr-meptyl), flusulfinam, fomesafen, foramsulfuron, glufosinate (including L- glufosinate and the ammonium salts of both), glyphosate (including the diammonium, isopropylammonium and potassium salts thereof), halauxifen (including halauxifen-methyl), haloxyfop (including haloxyfop-methyl), hexazinone, hydantocidin, icafolin (including icafolin-methyl), imazamox (including R-imazamox), imazapic, imazapyr, imazethapyr, indaziflam, indolauxipyr (including indolauxipyr-cyanomethyl), iodosulfuron (including iodosulfuron-methyl-sodium), iofensulfuron (including iofensulfuron-sodium), ioxynil, iptriazopyrid, isoproturon, isoxaflutole, lancotrione, MCPA, MCPB, mecoprop-P, mesosulfuron (including mesosulfuron-methyl), mesotrione, metamitron, metazachlor, methiozolin, metolachlor, metosulam, metribuzin, metsulfuron, napropamide, nicosulfuron, norflurazon, oxadiazon, oxasulfuron, oxyfluorfen, paraquat dichloride, pendimethalin, penoxsulam, phenmedipham, picloram, pinoxaden, pretilachlor, primisulfuron-methyl, prometryne, propanil, propaquizafop, propyrisulfuron, propyzamide, prosulfocarb, prosulfuron, pyraclonil, pyraflufen (including pyraflufen-ethyl), pyraquinate, pyrasulfotole, pyridate, pyriftalid, pyriflubenzoxim, pyrimisulfan, pyroxasulfone, pyroxsulam, quinclorac, quinmerac, quizalofop (including quizalofop-P-ethyl and quizalofop-P-tefuryl), rimisoxafen, rimsulfuron, saflufenacil, sethoxydim, simazine, S-metalochlor, sulfentrazone, sulfosulfuron, tebuthiuron, tefuryltrione, tembotrione, terbuthylazine, terbutryn, tetflupyrolimet, thiencarbazone, thifensulfuron, tiafenacil, tolpyralate, topramezone, tralkoxydim, triafamone, triallate, triasulfuron, tribenuron (including tribenuron-methyl), triclopyr, trifloxysulfuron (including trifloxysulfuron-sodium), trifludimoxazin, trifluralin, triflusulfuron, tripyrasulfone, 3-(2-chloro-4- fluoro-5-(3-methyl-2,6-dioxo-4-trifluoromethyl-3,6-dihydropyrimidin-1 (2H)-yl)phenyl)-5-methyl-4,5- dihydroisoxazole-5-carboxylic acid ethyl ester, 4-hydroxy-1 -methoxy-5-methyl-3-[4-(trifluoromethyl)-2- pyridyl]imidazolidin-2-one, 4-hydroxy-1 ,5-dimethyl-3-[4-(trifluoromethyl)-2-pyridyl]imidazolidin-2-one, 5-ethoxy-4-hydroxy-1 -methyl-3-[4-(trifluoromethyl)-2-pyridyl]imidazolidin-2-one, 4-hydroxy-1 -methyl-3- [4-(trifluoromethyl)-2-pyridyl]imidazolidin-2-one, 4-hydroxy-1 ,5-dimethyl-3-[1 -methyl-5-

[0125] (trifluoromethyl)pyrazol-3-yl]imidazolidin-2-one, (4R)1 -(5-tert-butylisoxazol-3-yl)-4-ethoxy-5-hydroxy-3- methyl-imidazolidin-2-one, (1 F?S,5SF?)-3-[2-methoxy-4-(prop-1 -yn-1 -yl)phenyl]-4-oxobicyclo[3.2.1 ]oct- 2-en-2-yl methyl carbonate, ethyl-2-[[3-[[3-chloro-5-fluoro-6-[3-methyl-2,6-dioxo-4- (trifluoromethyl)pyrimidin-l -yl]-2-pyridyl]oxy]acetate, methyl 2-[2-[2-bromo-4-fluoro-5-[3-methyl-2,6- dioxo-4-(trifluoromethyl)pyrimidin-1 -yl]phenoxy]phenoxy]-2-methoxy-acetate, 6-chloro-4-(2,7-dimethyl-

[0126] 1 -naphthyl)-5-hydroxy-2-methyl-pyridazin-3-one, (2-fluorophenyl)methyl 6-amino-5-chloro-2-(4-chloro-

[0127] 2-fluoro-3-methoxy-phenyl)pyrimidine-4-carboxylate, 6-amino-5-chloro-2-(4-chloro-2-fluoro-3- methoxy-phenyl)pyrimidine-4-carboxylic acid, and methyl 3-[2-chloro-5-[3,6-dihydro-3-methyl-2,6- dioxo-4-(trifluoromethyl)-1 (2H)-pyrimidinyl]-4-fluorophenyl]-3a,4,5,6-tetrahydro-6-methyl-6aH- cyclopent[d]isoxazole-6a-carboxylate.

[0128] The weight ratio of the polymorphs of the invention and another herbicide is selected as to give the desired, for example, synergistic action. The weight ratio is generally between 100:1 and 1 :1000, more preferably between 50:1 and 1 :500, for example between 50:1 and 1 :250, between 25:1 and 1 :125, between 10:1 and 1 :66, between 5:1 and 1 :33, and preferably between 1 :1 and 1 : 33.

[0129] The compounds or mixtures of the present invention can also be used in combination with one or more herbicide safeners. Examples of such safeners include benoxacor, cloquintocet (including cloquintocet- mexyl), cyprosulfamide, dichlormid, fenchlorazole (including fenchlorazole-ethyl), fenclorim, fluxofenim, furilazole, isoxadifen (including isoxadifen-ethyl), mefenpyr (including mefenpyr-diethyl), metcamifen and oxabetrinil.

[0130] Accordingly, the present invention provides for the use of a composition according to the present invention together with one or more pesticides, plant nutrients or plant fertilizers. The combination may also encompass specific plant traits incorporated into the plant using any means, for example conventional breeding or genetic modification.

[0131] 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, 15thEdition, British Crop Protection Council, 2009.

[0132] Various aspects and embodiments of the present invention will now be illustrated in more detail by way of example and the following Figures in which:

[0133] Fig. 1 shows the powder X-ray diffraction patterns of the polymorph of formula (I) designated Form 1 . Fig. 2 shows a DSC measurement of the polymorph of formula (I) designated Form 1 . Fig. 3 shows the Infrared Absorption Spectrum of the polymorph of formula (I) designated Form 1 . Fig. 4 shows a microscopic depiction of the milled amorphous material (Fig. 4A), and the milled polymorphic material (Fig. 4B) of the polymorph of formula (I) designated Form 1 .

[0134] Fig. 5 shows the powder X-ray diffraction patterns of the polymorph of formula (I) designated Form 2. Fig. 6 shows a DSC Measurement of the polymorph of formula (I) designated Form 2.

[0135] Fig. 7 shows the Infrared Absorption Spectrum of the polymorph of formula (I) designated Form 2.

[0136] Fig. 8 shows a microscopic depiction of the milled amorphous material (Fig. 8A), and the milled polymorphic material (Fig. 8B) of the polymorph of formula (I) designated Form 2.

[0137] EXAMPLES

[0138] The following, non-limiting examples illustrate the present invention:

[0139] EXAMPLE 1 - Preparation of Polymorphs

[0140] The compound of formula (I) was made according to the methods described in WO 2016 / 095768 and WO 2000 / 063613. Each method led to the production of an amorphous solid material.

[0141] EXAMPLE 1a - Preparation of Polymorph designated Form 1

[0142] Polymorph Form 1 was prepared by adding 3mL of a mixture of ethanol and water (at a ratio of 90:10) to 0.5038g of the compound of formula (I) as a 20% solution by weight / volume.

[0143] The resulting solution was heated to 50 °C at a rate of 0.2 °C / min whilst stirring at 500rpm until no crystalline solids remained before cooling at 0.2 °C / min to -10 °C and holding at that temperature for 12 hours. Upon cooling an oil phase formed, which was left undisturbed until crystal growth occurred at -10 °C. Crystals were observed after at least 12 hours, and a single-crystal X-ray diffraction analysis confirmed the presence of the polymorph Form 1 of the invention.

[0144] The experiment was successfully repeated with a 10% solution w / w of the compound of formula (I).

[0145] EXAMPLE 1b - Preparation of Polymorph Designated Form 2

[0146] Polymorph Form 2 was prepared by adding 3 mL of a mixture of methylcyclohexane and toluene (at a ratio of 70:30) to 0.5038g of the compound (I) to make a 20% solution by weight / volume.

[0147] The resulting solution was heated to 70 °C at a rate of 0.2 °C / min whilst stirring at 500 rpm until no crystalline solids remained, followed by cooling at 0.2 °C / min to -10 °C, and holding at that temperature for 12 hours. Upon cooling an oil phase formed, which was left stirring until crystal growth occurred at - 10 °C. Crystals were observed after 12 hrs, and single-crystal electron diffraction analysis confirmed the presence of the polymorph Form 2 of the invention.

[0148] In the above Example 1 b, crystals were observed after 12hrs, but since this is a nucleation event it is stochastic in nature, there is generally an increased chance of observing crystals if the system is left stirring for longer.

[0149] The experiment was successfully repeated with a 10% solution w / vol of the compound of formula (I) as well as other methylcyclohexane and toluene volume ratios such as 80:20 and 75:25.

[0150] EXAMPLE 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 electron diffraction and / or differential scanning calorimetry (DSC).

[0151] Powder X-ray diffraction analysis of solid material was carried out using the the Malvern Panalytical Empyrean pXRD diffractometer at room temperature between 21 °C to 26 °C and at relative humidity above 40%.

[0152] Samples were mounted in XRD sample holders and the samples flattened with a microscope slide. The pXRD holder was placed in the instrument, spun and the powder pattern collected from 3.5° to 40° 2- theta with 0.0167° step size and 23 seconds exposure time.

[0153] Differential scanning calorimetry (DSC) analysis was carried out using a Mettler Toledo DSC1 and TA DSC2500. 1 to 7 mg of sample was weighed into the DSC crucible, the crucible was sealed and then analysed. The temperature profile for the analysis was 25 °C to 160 °C at a heating rate of 10 °C / min. The lid of the DSC crucible was pierced to allow the escape of any gas formed during the heating of the sample.

[0154] EXAMPLE 2a - Analysis of Polymorph Designated Form 1

[0155] Measured powder X-ray diffraction pattern for polymorph Form 1 of the invention are shown in Fig. 1 . 2-Theta and d-spacing values measured for the crystalline Form 1 of the present invention can be found in Table 3 below.

[0156] TABLE 3

[0157] Key: VS: Very strong, S: Strong, M: Medium, W:Weak The DSC analysis confirmed the presence of the polymorph designated Form 1 of the invention with a melting point of 81 °C. A DSC trace of the polymorph Form 1 is shown in Fig. 2.

[0158] Infra-red (IR) analysis was carried out using a ThermoScientific™ Nicolet iS5 FT-IR Spectrometer with an iD7 ATR attachment. The analysis was performed using a scan range of 350-4000 cm1’ with 16 repeat scans. A background scan was measured with no sample present, before adding 1 -1 Omg of sample to cell.

[0159] An IR spectrum of polymorph designated Form 1 of the invention is shown in Fig. 3. EXAMPLE 2b - Analysis of Polymorph Designated Form 2

[0160] Measured powder X-ray diffraction pattern for polymorph Form 2 of the invention are shown in Fig. 5. 2-Theta and d-spacing values measured for the crystalline Form 2 of the present invention can be found in Table 4 below.

[0161] TABLE 4

[0162] Key: VS: Very strong, S: Strong, M: Medium, W:Weak

[0163] The DSC analysis confirmed the presence of the polymorph Form 2 of the invention with a melting point of 70°C. A DSC trace of the polymorph Form 2 is shown in Fig. 6. Infra-red (IR) analysis was carried out using a ThermoScientific™ Nicolet iS5 FT-IR Spectrometer with an iD7 ATR attachment. The analysis was performed using a scan range of 350-4000 cm1’ with 16 repeat scans. A background scan was measured with no sample present, before adding 1 -1 Omg of sample to cell.

[0164] An IR spectrum of polymorph Form 2 of the invention is shown in Fig. 7.

[0165] EXAMPLE 3 - Stability of Polymorphs

[0166] Amorphous material and the polymorphic material according to the invention were subjected to storage at different temperatures and humidity levels. The amorphous material failed the test at both 25 °C and 40 °C after 1 week in the sense that sticky or glassy material was formed. Conversely, the crystalline material was stable and remained free-flowing even after 4 weeks:

[0167] TABLE 5: Status after 1 week (Amorphous) and 4 weeks (Crystalline) on storage at varying relative humidity (RH) and temperature

[0168] Milling: Effect of Crystalline Forms vs. Amorphous Form

[0169] SC formulations (target 10%w / v) were prepared at the same scale using the same recipe and the same shaker mill with grinding beads before filtering to remove the formulation from the grinding media. Use of the crystalline form provided clear advantages over the amorphous form in terms of ease of milling and final active ingredient concentration, as set out in the table below.

[0170] This difference was also clear from the microscopy, wherein the crystalline material resulted in a lower particle size, and better dispersion. This difference is shown in Fig. 4 for the polymorph designated Form 1 , and in Fig. 8 for the polymorph designated Form 2.

[0171] In summary, the novel crystalline polymorphic forms Form 1 and Form 2 of compound (I) represent more stable and useful materials compared to the amorphous form, whilst preserving biological activity.

[0172] 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 scope of the invention, which is defined and circumscribed by the appended claims.

Claims

CLAIMS1 . A crystalline polymorph of the compound of formula (I)designated Form 1 , which has the following lattice parameters: a = 55.3 A ± 0.5 A, b = 9.4 A ± 0.5 A, c=24.9 A ± 0.5 A, a = 90° ± 0.1 °, p = 98.6° ± 0.1 °, y = 90° ± 0.1 °, and volume = 12728 A3± 127 A3.

2. The crystalline polymorph according to claim 1 , wherein the polymorph is characterized by a powder X-ray diffraction pattern expressed in terms of 20 angles, wherein the powder X-ray diffraction pattern comprises: a) at least one 20 angle value at 6.5 ± 0.2, b) at least one 20 angle value at 7.2 ± 0.2, c) at least one 20 angle value at 7.4 ± 0.2, and d) at least one, preferably two, more preferably three, yet more preferably more than four 20 angle values selected from the group comprising: 8.9 ± 0.2, 12.9 ± 0.2, 14.3 ± 0.2, 14.8 ± 0.2, 16.1 ± 0.2, 17.3 ± 0.2, 19.4 ± 0.2, 20.5 ± 0.2, 23.5 ± 0.2, 25.0 ± 0.2, 26.2 ± 0.2, 28.2 ± 0.2, and 29.4 ± 0.2.

3. The crystalline polymorph according to claim 1 or claim 2, which has a melting point of 81 °C ± 5°C.

4. A crystalline polymorph of the compound of formula (I)designated Form 2, which has the following lattice parameters: a = 57.7 A ± 0.5 A, b = 9.5 A ± 0.5 A, c = 24.9 A ± 0.5 A, a = 90° ± 0.1 °, p = 96.0° ± 0.5°, y = 90° ± 0.1 °, and volume = 13532 A3± 135 A3, and is characterized in that is prepared by the following steps: ix) Adding a mixture of methylcyclohexane and toluene to the compound of formula (I);x) Heating and stirring the resulting mixture until the solids of the compound of formula (I) are dissolved; xi) Cooling the mixture gradually such that an oil phase is formed; and xii) Stirring the resulting oil phase until a crystalline polymorph is formed.

5. The crystalline polymorph according to claim 4, wherein the polymorph is further characterized by a powder X-ray diffraction pattern expressed in terms of 20 angles, wherein the powder X-ray diffraction pattern comprises: a) at least one 20 angle value at 6.1 ± 0.2, b) at least one 20 angle value at 7.0 ± 0.2, and c) at least one, preferably two, more preferably three 20 angle values selected from the group comprising 10.9 ± 0.2, 12.3 ± 0.2, 13.5 ± 0.2, 14.1 ± 0.2, 14.7 ± 0.2, 15.3 ± 0.2, 15.9 ± 0.2,16.9 ± 0.2, 17.1 ± 0.2, 19.4 ± 0.2, 19.7 ± 0.2, 20.1 ± 0.2, 20.4 ± 0.2, 20.8 ± 0.2, 21 .4 ± 0.2,23.4 ± 0.2, 24.1 ± 0.2, 25.0 ± 0.2, and 26.0 ± 0.2.

6. The crystalline polymorph according to claim 4 or claim 5, which has a melting point of 70°C ± 5°C.

7. An agricultural composition comprising: i) a polymorph designated Form 1 according to any one of claims 1 to 3; and ii) a polymorph designated Form 2 according to any one of claims 4 to 6.

8. An agricultural composition comprising at least one polymorph according to any one of claims 1 to 6, further comprising an amorphous form of the compound of formula (I).

9. An agricultural composition according to claim 7, further comprising an amorphous form of the compound of formula (I).

10. An agricultural composition comprising a polymorph according to any one of claims 1 to 6, and at least one agriculturally acceptable carrier or diluent.11 . The composition of claim 10, which further comprises at least one herbicide.

12. An agricultural composition according to any one of claims 7 to 11 , wherein the agricultural composition is a suspension concentrate formulation.

13. Use of a polymorph according to any one of claims 1 to 6, or a composition according to any one of claims 7 to 12 over crops that are resistant to the compound of formula (I).

14. Use of a polymorph according to any one of claims 1 to 6, or a composition according to any one of claims 7 to 12 to control weeds that are resistant to PPO herbicides except the compound of formula (I).

15. 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 composition comprising a polymorph according to any one of claims 1 to 6, or a composition according to any one of claims 7 to 12.