NEW CRYSTAL FORMS OF FORAMSULFURON MONOSODIUM SALT

Abstract

The present invention relates to a new crystalline form of the monosodium salt of foramsulfuron (formula i), a process for producing this crystalline form, its use in agrochemical preparations, defined compositions, mixtures or agrochemical preparations containing this crystalline form, as well as a new mono-methanol solvate of the monosodium salt of foramsulfuron.

Description

[0001] The present invention relates to a new crystalline form of the monosodium salt of foramsulfuron, a process for producing this crystalline form, its use in agrochemical preparations, and certain compositions, mixtures or agrochemical preparations containing this crystalline form, as well as a new mono-methanol solvate of the monosodium salt of foramsulfuron.

[0002] Foramsulfuron of the following formula (I) and its monosodium salt are known from EP 0 757 679 A1.

[0003] Foramsulfuron of formula (I) and certain salts of this compound are known herbicidal active ingredients, see "The Pesticide Manual", 16th edition, The British Crop Protection Council and the Royal Society of Chemistry, 2012.

[0004] Furthermore, it is known that foramsulfuron of formula (I) and its salts can be used in combination with other herbicidal active substances and / or with safeners, as described for example in EP 0 790 771 A1 or EP 1 104 239 A1.

[0005] Foramsulfuron has the molecular formula C 17 H 20 N 6 O 7 S, the CAS number 173159-57-4 and the IUPAC name 1-(4,6-dimethoxypyrimidin-2-yl)-3-[2-(dimethylcarbamoyl)-5-formamidophenylsulfonyl]urea, and is subsequently also referred to as N-[(4,6-Dimethoxypyridin-2-yl)-aminocarbonyl]-2-dimethylaminocarbonyl-5-formylaminobenzenesulfonamide.

[0006] The compound of formula (I) and its monosodium salt can be prepared by the methods described in EP 0 757 679 A1 and US 6,500,952 B1.

[0007] EP 1 902 618 A1 describes processes for the production of sulfonamide salts.

[0008] Until now, only one crystal form of the monosodium salt of foramsulfuron was known, which will be referred to below as crystal form A. This crystal form A corresponds to a semi-methanol solvate.

[0009] The crystal lattice of a solid can also be composed of several chemical components. If one of these is a liquid (e.g., a solvent), it is called a solvate.

[0010] The occurrence of active ingredients in different crystalline modifications (polymorphism) is of great importance for both the development of manufacturing processes and the formulation of agrochemical preparations. Besides their appearance (crystal habit) and hardness, the various crystalline modifications of a chemical compound also differ in numerous other physicochemical properties. Differences in stability, filterability, solubility, hygroscopicity, melting point, solid density, and flowability can have a significant impact on the quality and efficacy of plant protection products. It is currently not possible to predict the occurrence and number of crystalline modifications, including their physicochemical properties.In particular, thermodynamic stability and the differing behavior after administration to living organisms cannot be predicted. The above statements regarding polymorphism apply analogously to pseudopolymorphism.

[0011] The well-known crystal form A has some disadvantageous properties, which are briefly described below.

[0012] Crystal form A can adversely affect the stability or storage life of compositions (e.g., agrochemical formulations) containing crystal form A. This can occur because, for example, the chemical stability of crystal form A is insufficient in certain compositions, and / or the chemical stability of other components (such as other active ingredients) in these compositions is negatively affected by crystal form A, and its concentration in the composition decreases over time. It can also happen that a composition (e.g., an agrochemical formulation) containing crystal form A is unstable over a longer storage period, and the physical properties of the composition change, for example, the viscosity or flowability of the composition changes in an undesirable way.

[0013] Furthermore, it is known that sulfonylurea herbicides undergo chemical degradation reactions in the presence of certain excipients, such as alcoholic diluents, particularly methanol. This leads to a decrease in the active ingredient content of the sulfonylurea herbicides during prolonged storage, which is undesirable. This chemical degradation also occurs in compositions (such as mixtures or formulations) containing foramsulfuron and its salts in combination with other sulfonylurea herbicides or their salts, for example, in the compositions described in EP 1 104 239 A1. This applies particularly to more readily degradable / hydrolyzable sulfonylurea herbicides such as iodosulfuron, iodosulfuron-methyl, and their respective salts, such as iodosulfuron sodium or iodosulfuron-methyl sodium.

[0014] Furthermore, in some cases the technical handling of the known crystal form A is difficult. For example, according to the manufacturing process described in EP 0 757 679 A1, this crystal form A occurs in the form of flaky aggregates that are very difficult to filter.

[0015] The invention is therefore based on the objective of remedying one, several or all of the disadvantages mentioned above in connection with the known crystal form A, or of improving the adverse properties mentioned above in connection with the known crystal form A.

[0016] This problem is solved according to the invention by a new crystal form of the monosodium salt of the compound of formula (I) with the molecular formula C 17 H 19 N 6 O 7 SNa, which is hereinafter referred to as crystal form B.

[0017] The invention therefore primarily relates to the monosodium salt of foramsulfuron in crystalline form (crystal form B), characterized in that the X-ray powder diffractogram of this salt, when using Cu Kα radiation at 25°C, exhibits at least 3 of the following 2Θ (2 Theta) values: 2Θ (2Theta) values ​​in° 6.2 6.4 14.4 14.6 14.7 18.4 19.2 20.1 23.2 24.7

[0018] This crystal form B according to the invention is characterized in that it has an X-ray powder diffractogram with the reflection positions 2Θ (2 Theta) specified in Table 1. The X-ray powder diffractogram of crystal form B is also shown in the Figure 2 The most intense and characteristic signals 2Θ (2 Theta) of the X-ray powder diffractogram of crystal form B are at 6.2, 6.4, 14.4, 14.6, 14.7, 18.4, 19.2, 20.1, 23.2, and 24.7° (each ± ​​0.2°).

[0019] Preferably, the crystal form B according to the invention is characterized in that the X-ray powder diffractogram of this salt, when using Cu Kα radiation at 25 °C, has at least 4, preferably at least 5, preferably at least 6, further preferably at least 7, particularly preferably at least 8, and in particular preferably all of the most intense signals 2Θ (2 Theta) specified above.

[0020] The crystal form B according to the invention is preferably characterized in that the X-ray powder diffractogram of this salt, when using Cu Kα radiation at 25 °C, additionally exhibits at least two, four, six, eight, ten, twelve or more, preferably at least 15, 20, 23, 25, 27, 30, 33, 35, 38, 40, 42, 44, 46, 48, 50 or more, preferably all, of the following 2Θ (2 Theta) values: 10.3 10.5 11.1 11.3 11.4 12.0 12.1 12.4 12.6 12.9 13.6 14.0 15.0 15.1 15.4 16.0 16.2 17.0 17.2 18.2 18.8 20.3 20.6 20.8 21.2 21.6 22.7 23.7 24.6 25.4 25.9 26.2 26.9 27.1 27.7 28.3 29.0 30.2 30.5 30.7 31.0 31.2 31.9 32.5 32.6 33.7 34.8 35.6 35.9 36.2 36.4 36.9 37.4

[0021] The crystal form B according to the invention, unlike the crystal form C described below, is not hygroscopic and exhibits improved stability in formulations (agrochemical preparations).

[0022] The crystal form B according to the invention is better suited for the production of (storage) stable formulations, and it is more compatible with other sulfonylurea herbicides and their salts, in particular with iodosulfuron and its salts, since sulfonylurea herbicides (especially iodosulfuron) and their salts exhibit unsatisfactory stability, in particular unsatisfactory chemical stability, when mixed with crystal form A.

[0023] All X-ray powder diffractometry data presented in this text refer to the following measurement parameters: Scan axis Gonio Scan mode transmission Starting position [°2Theta] 2.0066 End position [°2Theta] 37.9906 Anode material Cu Wavelength K-Alphal [Å] 1.54060 Wavelength K-Alpha2 [Å] 1.54443 Wavelength K-Beta [Å] 1.39225 K-A2 / K-A1 ratio 0.50000 generator 40 mA, 40 kV Incident Beam Monochromator focusing x-xay mirror Spinning Yes Specification of 2Θ (2 Theta) values ± 0,2°

[0024] Furthermore, within the scope of the present invention, the crystalline form hereinafter referred to as crystal form C was found. This is the mono-methanol solvate of the monosodium salt of the compound of formula (I). Crystal form C can be obtained, for example, by storing crystal form A with methanol for an extended period of time; in this process, crystal form A transforms into crystal form C. Crystal form C is described in detail below.

[0025] Crystal forms A, B, and C are characterized by different X-ray powder diffractograms. Table 1 below lists the most intense, characteristic reflection positions 2Θ (2 Theta), while Table 3 below shows all reflection positions 2Θ (2 Theta). Table 1: Characteristic reflection positions - X-ray diffractometry of crystal forms A, B and C (as above) defined) Peak maximum [2 Theta], expressed in ° Crystal form A Crystal form B Crystal form C 7.4 6.2 9.1 8.7 6.4 9.1 9.0 14.4 9.7 9.2 14.6 12.6 9.3 14.7 16.2 15.7 18.4 18.5 23.3 19.2 24.1 23.3 20.1 24.3 23.6 23.2 24.6 26.0 24.7

[0026] If the reflection positions 2Θ (2 Theta) of the X-ray powder diffractograms given in this text for a given crystalline form exhibit the same value twice (such as the 2Θ peak maximum at 23.3° in the case of crystal form A), then these are two closely spaced peaks. While rounding the measured value of the respective peak maximum to one decimal place can result in two peaks with the same value, the X-ray powder diffractogram actually shows two separate peaks.

[0027] The X-ray powder diffractogram of crystal form A is in Figure 1 reproduced.

[0028] The X-ray powder diffractogram of crystal form B is in Figure 2 reproduced.

[0029] The X-ray powder diffractogram of crystal form C is in Figure 3 reproduced.

[0030] The monosodium salt of foramsulfuron according to the invention is particularly preferred in crystalline form, characterized in that the X-ray powder diffractogram when using Cu Kα radiation at 25 °C essentially corresponds to that described in Figure 2 corresponds to the reproduced spectrum.

[0031] Crystal forms A, B, and C are characterized by different Raman spectra. The most intense, characteristic bands for each are listed in Table 2 below.

[0032] All Raman spectroscopy data given in this text refer to the following measurement parameters, where the position of the band maxima of the wavenumber is given in cm⁻¹: Device Bruker Raman RFS 100 / S Number of scans 64 resolution 2 - 4 cm -1< Laser Power 50 mW Laser wavelength 1064 nm

[0033] The crystal form B according to the invention is preferably characterized in that its Raman spectrum has at least the following bands: Band maximum [cm -1< ] 2959 2915 1686 1587 1526 694 345 133

[0034] Preferably, the Raman spectrum of the crystal form B according to the invention has at least ten of the bands listed in Table 4 below, preferably 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65 or more, preferably all of the bands listed in Table 4 below. Table 2: Characteristic bands of the Raman spectra of crystal forms A, B and C (as defined above) Band maximum [cm -1< ] Crystal form A Crystal form B Crystal form C 2941 2959 3090 1700 2915 2943 1320 1686 2919 1250 1587 1593 990 1526 1576 697 694 691 362 345 156 103 133 122

[0035] The Raman spectrum of crystal form A is in Figure 4 reproduced.

[0036] The Raman spectrum of crystal form B is in Figure 5 reproduced.

[0037] The Raman spectrum of crystal form C is in Figure 6reproduced. Preferably, the Raman spectrum of the crystal form B according to the invention corresponds essentially to that shown in Figure 5 reproduced spectrum. Table 3: X-ray diffractometry of crystal forms A, B and C (as defined above) Peak maximum [2 Theta] Crystal form A Crystal form B Crystal form C 5.6 6.2 9.1 5.9 6.4 9.1 7.4 10.3 9.7 7.6 10.5 12.0 7.9 11.1 12.6 8.4 11.3 14.8 8.7 11.4 15.7 9.0 12.0 16.2 9.2 12.1 16.3 9.3 12.4 17.8 11.1 12.6 18.0 11.6 12.9 18.2 11.8 13.6 18.5 13.2 14.0 19.0 13.4 14.4 19.5 13.9 14.6 19.9 14.5 14.7 20.1 14.8 15.0 20.9 15.3 15.1 21.1 15.5 15.4 21.7 15.7 16.0 22.1 16.1 16.2 22.6 16.7 17.0 23.5 17.0 17.2 23.8 17.3 18.2 24.1 18.1 18.4 24.3 19.0 18.8 24.5 19.2 19.2 24.6 19.7 20.1 25.1 20.7 20.3 25.6 20.9 20.6 25.8 21.3 20.8 26.5 22.3 21.2 26.8 22.6 21.6 27.1 22.8 22.7 28.8 23.3 23.2 29.2 23.3 23.7 29.7 23.6 24.6 30.0 24.5 24.7 30.5 24.8 25.4 30.8 25.1 25.9 31.3 26.0 26.2 31.7 26.8 26.9 31.9 27.6 27.1 32.0 28.2 27.7 33.1 28.7 28.3 33.2 29.1 29.0 33.5 30.1 30.2 34.2 30.7 30.5 34.4 32.0 30.7 34.9 33.0 31.0 35.4 34.4 31.2 35.8 37.0 31.9 36.2 37.4 32.5 36.6 32.6 37.2 33.7 37.7 34.8 35.6 35.9 36.2 36.4 36.9 37.4 Table 4: Raman spectroscopy bands of crystal forms A, B and C (as defined above) Band maximum [cm -1< ] Crystal form A Crystal form B Crystal form C 3114 3338 3302 3097 3100 3090 3072 3061 3030 3032 3035 3016 2941 3018 2999 2890 2959 2943 2878 2915 2919 2842 2865 2870 2798 2810 2839 1700 1686 2812 1691 1654 1693 1653 1628 1628 1639 1604 1617 1604 1587 1607 1537 1526 1593 1513 1478 1576 1449 1451 1533 1404 1421 1517 1382 1393 1480 1320 1372 1449 1267 1304 1415 1250 1262 1404 1218 1244 1384 1196 1216 1372 1160 1206 1303 1150 1175 1261 1120 1142 1243 1101 1112 1215 1053 1092 1207 1004 1064 1168 990 1048 1148 936 1031 1137 926 1022 1111 896 1002 1092 760 983 1074 744 938 1048 697 925 1031 684 910 1015 642 904 1002 598 882 984 555 864 940 534 823 924 500 812 908 446 786 895 424 763 883 362 735 837 310 713 826 294 694 788 263 688 761 215 649 739 159 623 710 103 614 691 85 594 649 580 620 555 593 512 581 464 517 445 469 421 431 394 394 356 370 345 347 254 333 218 283 186 266 147 242 133 156 98 122 84 82

[0038] In a further aspect, the present invention relates to a composition containing the crystal form B according to the invention in a total amount of at least 5 wt.%, wherein this total amount is preferably at least 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 wt.% or more, in each case based on the total amount of monosodium salt of foramsulfuron contained in the composition.

[0039] Such a composition according to the invention is preferably characterized in that the composition contains the crystal form B according to the invention in a total amount of at least 10 wt.%, preferably 15 wt.% or more, in each case based on the total amount of monosodium salt of foramsulfuron contained in the composition.

[0040] A preferred composition according to the invention is characterized in that it is in solid form at 25 °C and 1013 mbar, and / or the content of monosodium salt of foramsulfuron is 80 wt.% or more, preferably 85 wt.% or more, more preferably 90 wt.% or more, particularly preferably 95 wt.% or more, in each case based on the total weight of the composition.

[0041] A preferred composition according to the invention is characterized in that the composition contains the crystal form B according to the invention in a total amount of at least 25 wt.%, preferably 40 wt.% or more, in each case based on the total amount of monosodium salt of foramsulfuron contained in the composition, and the content of monosodium salt of foramsulfuron is 80 wt.% or more, preferably 85 wt.% or more, in each case based on the total weight of the composition.

[0042] A particularly preferred composition according to the invention is characterized in that the composition contains the crystal form B according to the invention in a total amount of at least 50 wt.%, preferably 60 wt.% or more, in each case based on the total amount of monosodium salt of foramsulfuron contained in the composition, and the content of monosodium salt of foramsulfuron is 85 wt.% or more, preferably 90 wt.% or more, in each case based on the total weight of the composition.

[0043] A particularly preferred composition according to the invention is characterized in that the composition contains the crystal form B according to the invention in a total amount of at least 70 wt.%, preferably 80 wt.% or more, in each case based on the total amount of monosodium salt of foramsulfuron contained in the composition, and the content of monosodium salt of foramsulfuron is 85 wt.% or more, preferably 90 wt.% or more, in each case based on the total weight of the composition.

[0044] A particularly preferred composition according to the invention is characterized in that the composition contains the crystal form B according to the invention in a total amount of at least 80 wt.%, preferably 85 wt.% or more, in each case based on the total amount of monosodium salt of foramsulfuron contained in the composition, and the content of monosodium salt of foramsulfuron is 90 wt.% or more, preferably 95 wt.% or more, in each case based on the total weight of the composition.

[0045] One of the most particularly preferred embodiments is a composition according to the invention characterized in that the composition contains the crystal form B according to the invention in a total amount of at least 90 wt.%, preferably 95 wt.% or more, in each case based on the total amount of monosodium salt of foramsulfuron contained in the composition, and the content of monosodium salt of foramsulfuron is 90 wt.% or more, preferably 95 wt.% or more, in each case based on the total weight of the composition.

[0046] In a further aspect, the present invention relates to the use of the crystal form B according to the invention or a composition according to the invention as defined above for the production of agrochemical preparations, preferably for the production of herbicidally effective agrochemical preparations.

[0047] In another aspect, the present invention relates to the mono-methanol solvate of the monosodium salt of foramsulfuron in crystalline form (crystal form C), characterized in that the X-ray powder diffractogram of this salt, when using Cu Kα radiation at 25 °C, exhibits at least 3 of the following 2Θ (2 Theta) values: 2Θ (2 Theta) values ​​in ° 9.1 9.1 9.7 12.6 16.2 18.5 24.1 24.3 24.6

[0048] Preferably, the X-ray powder diffractogram of the crystal form C according to the invention, when using Cu Kα radiation at 25 °C, exhibits at least 4, preferably at least 6, preferably at least 8, more preferably all of the aforementioned 2Θ (2 Theta) values.

[0049] Further preferably, the X-ray powder diffractogram of the crystal form C according to the invention, when using Cu Kα radiation at 25 °C, additionally exhibits at least two, four, six, eight, ten, twelve or more, preferably at least 15, 20, 23, 25, 27, 30, 33, 35, 38, 40, 42, 44, 46, 48, 50 or more, preferably all, of the following 2Θ (2 Theta) values: 12.0 14.8 15.7 16.3 17.8 18.0 18.2 19.0 19.5 19.9 20.1 20.9 21.1 21.7 22.1 22.6 23.5 23.8 24.5 25.1 25.6 25.8 26.5 26.8 27.1 28.8 29.2 29.7 30.0 30.5 30.8 31.3 31.7 31.9 32.0 33.1 33.2 33.5 34.2 34.4 34.9 35.4 35.8 36.2 36.6 37.2 37.7

[0050] The crystal form C according to the invention is preferably characterized in that its Raman spectrum has at least the following bands: Band maximum [cm -1< ] 3090 2943 2919 1593 1576 691 156 122

[0051] Preferably, the Raman spectrum of the crystal form C according to the invention has at least ten of the bands listed in Table 4, preferably 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65 or more, preferably all of the bands listed in Table 4.

[0052] Preferably, the Raman spectrum of the crystal form C according to the invention corresponds essentially to that in Figure 6 reproduced spectrum.

[0053] Furthermore, the present invention relates to a composition containing the crystal form C in a total amount of at least 5 wt.%, wherein this total amount is preferably at least 10, 15, 20, 25, 30, 35, 40, 45, 50, 55, 60, 65, 70, 75, 80, 85, 90, 95 wt.% or more, in each case based on the total amount of monosodium salt of foramsulfuron contained in the composition.

[0054] Preferably, the present invention relates to a composition containing crystal form C (as defined above), wherein the composition is in solid form at 25°C and 1013 mbar, and / or the monosodium salt content of foramsulfuron is 80 wt.% or more, wherein preferably the monosodium salt content of foramsulfuron is 85 wt.% or more, more preferably 90 wt.% or more, and most preferably 95 wt.% or more, in each case based on the total weight of the composition.

[0055] The crystal form B according to the invention can be produced by the methods described below.

[0056] The invention further relates to a process for producing crystal form B, comprising step (a) suspending a monosodium salt of foramsulfuron (preferably of crystal form A), crystal form C, or a mixture of these substances, in a diluent or diluent mixture, wherein the diluent or diluent mixture used in step (a) is selected from the group consisting of alcohols with 3 to 6 carbon atoms, preferably primary alcohols with 3 to 6 carbon atoms, and ketones with 3 to 6 carbon atoms, and mixtures thereof, or consists of at least 20 wt.%, preferably at least 30 wt.%, more preferably at least 40 wt.%, and even more preferably at least 50 wt.% thereof.

[0057] The crystal form B according to the invention can be obtained if the diluent or diluent mixture used in the above-described process contains 20 wt.% or more of alcohols with 3 to 6 C atoms and / or ketones with 3 to 6 C atoms.

[0058] It is preferred that the diluent or diluent mixture used in the above-described process contains 60 wt.% or more of alcohols with 3 to 6 carbon atoms and / or ketones with 3 to 6 carbon atoms, since this results in crystals that are easier to filter, which is a considerable advantage in terms of process engineering.

[0059] The invention therefore relates in particular to a process for producing crystal form B, comprising step (a) suspending a monosodium salt of foramsulfuron (preferably of crystal form A), of crystal form C, or of a mixture of these substances, in a diluent or diluent mixture, wherein the diluent or diluent mixture used in step (a) is selected from the group consisting of alcohols with 3 to 6 carbon atoms, preferably primary alcohols with 3 to 6 carbon atoms, and ketones with 3 to 6 carbon atoms, and mixtures thereof, or consists of at least 60 wt.% thereof.

[0060] The invention further relates to a method for producing crystal form B, comprising the step (a) Suspension of foramsulfuron in a diluent or diluent mixture, (b) Reaction of foramsulfuron with a sodium-containing base, preferably an organic base, preferably sodium methylate and / or sodium ethylate, wherein the diluent or diluent mixture used in step (a) is selected from the group consisting of alcohols with 3 to 6 C atoms, preferably primary alcohols with 3 to 6 C atoms, and ketones with 3 to 6 C atoms, and mixtures thereof, or consists of at least 20 wt.%, preferably at least 30 wt.%, further preferably at least 40 wt.%, and even more preferably at least 50 wt.% thereof.

[0061] The invention relates in particular to a method for producing crystal form B, comprising the step (a) Suspension of foramsulfuron in a diluent or diluent mixture, (b) Reaction of foramsulfuron with a sodium-containing organic base, preferably sodium methylate and / or sodium ethylate, wherein the diluent or diluent mixture used in step (a) is selected from the group consisting of alcohols having 3 to 6 C atoms, preferably primary alcohols having 3 to 6 C atoms, and ketones having 3 to 6 C atoms, and mixtures thereof, or consists of at least 60 wt% thereof.

[0062] Preferably, in step (b) sodium methylate in methanol and / or sodium ethylate in ethanol is used as the sodium-containing organic base.

[0063] The processes according to the invention for producing crystal form B are preferably carried out in such a way that the diluent or diluent mixture used in step (a) is selected from the group consisting of alcohols with 3 to 6 C atoms, preferably primary alcohols with 3 to 6 C atoms, and ketones with 3 to 6 C atoms, and mixtures thereof, or consists of at least 60 wt.%, preferably 70 wt.% or more, more preferably 80 wt.% or more, further preferably 90 wt.% or more, particularly preferably 95 wt.% or more.

[0064] The processes according to the invention for producing the crystal form B are preferably carried out in such a way that the diluent or diluent mixture used in step (a) is selected from the group consisting of 1-butanol, acetone, methyl isobutyl ketone, and mixtures thereof, or consists of 60 wt.% or more (preferably 70 wt.% or more, more preferably 80 wt.% or more, further preferably 90 wt.% or more, particularly preferably 95 wt.% or more).

[0065] The processes according to the invention for producing crystal form B are preferably carried out at temperatures of at least 0 °C. Preferably, the processes according to the invention for producing crystal form B are carried out at temperatures in the range of 0 to 150 °C, more preferably at temperatures in the range of 25 to 130 °C.

[0066] The processes according to the invention for producing crystal form B are preferably carried out at temperatures of at least 25 °C, preferably at least 30 °C, and preferably at least 40 °C. More preferably, the processes according to the invention for producing crystal form B are carried out at temperatures in the range of 40 to 150 °C, preferably at temperatures in the range of 45 to 130 °C, and particularly preferably in the range of 50 to 120 °C.

[0067] In particularly preferred processes according to the invention for producing crystal form B, acetone is used in step (a) as a diluent or as the diluent. In this case, the processes according to the invention are preferably carried out at temperatures in the range of 0 to 65 °C, preferably in the range of 25 to 56 °C.

[0068] In further particularly preferred processes according to the invention for producing crystal form B, acetone is used in step (a) as a diluent or as the diluent. In this case, the processes according to the invention are preferably carried out at temperatures in the range of 40 to 65 °C, preferably in the range of 45 to 56 °C, and particularly preferably in the range of 50 to 56 °C.

[0069] The processes according to the invention for producing crystal form B are preferably carried out such that the weight ratio of the total amount of foramsulfuron, crystal form A, and crystal form C to the total amount of the diluent or diluent mixture used in step (a) is less than 2:1. Preferably, the weight ratio of the total amount of foramsulfuron, monosodium salts of foramsulfuron (preferably of crystal form A), and crystal form C to the total amount of the diluent or diluent mixture used in step (a) is in the range of 3:1 to 1:20, more preferably in the range of 2:1 to 1:15, and more preferably in the range of 1:1 to 1:10. In many cases, this weight ratio is preferably in the range of 2:3 to 1:8, and particularly in the range of 1:2 to 1:5.

[0070] The inventive method for producing the inventive crystal form B preferably comprises further steps, preferably cooling the resulting mixture containing crystal form B. The cooling preferably takes place over a period of at least 15 minutes, more preferably over a period of at least 30 minutes.

[0071] The cooling process preferably takes place over a period of at least 60 minutes, even more preferably over a period of at least 120 minutes, and particularly preferably over a period of at least 180 minutes.

[0072] The inventive method for producing the crystal form B according to the invention preferably comprises further steps, preferably

[0073] Filtration of the resulting mixture containing crystal form B, and / or isolation of crystal form B, and / or drying of crystal form B.

[0074] Within the framework of the inventive process for producing the inventive crystal form B, it is preferred if the starting material used, preferably crystal form A and / or crystal form C, is dissolved in the diluent only to a very small extent, and in particular – in contrast to recrystallization processes – is not completely dissolved, but rather a solid-to-solid transformation of the starting material into crystal form B takes place, i.e., a transformation of solid substances. A mixture comprising is further described. (i) monosodium salt of foramsulfuron and / or a solvate thereof, preferably comprising crystal form A, crystal form B, crystal form C, or a mixture comprising two or all of these crystal forms, and (ii) a diluent or diluent mixture selected from the group consisting of alcohols having 3 to 6 carbon atoms, preferably primary alcohols having 3 to 6 carbon atoms, and carbon dioxide having 3 to 6 carbon atoms, and mixtures thereof, or comprising at least 20 wt%, preferably at least 30 wt%, further preferably at least 40 wt%, and even more preferably at least 50 wt% thereof.

[0075] In particular, a mixture is described, comprising (i) monosodium salt of foramsulfuron and / or a solvate thereof, preferably comprising crystal form A, crystal form B, crystal form C, or a mixture comprising two or all of these crystal forms, and (ii) a diluent or diluent mixture selected from the group consisting of alcohols having 3 to 6 carbon atoms, preferably primary alcohols having 3 to 6 carbon atoms, and ketones having 3 to 6 carbon atoms, and mixtures thereof, or comprising at least 60 wt.% thereof, and preferably comprising 70 wt.% or more, more preferably 80 wt.% or more, further preferably 90 wt.% or more, particularly preferably 95 wt.% or more thereof.

[0076] Preferably, the diluent or diluent mixture of such a mixture according to the invention is selected from the group consisting of 1-butanol, acetone, methyl isobutyl ketone, and mixtures thereof, or it consists of at least 60 wt.% (preferably 70 wt.% or more, more preferably 80 wt.% or more, further preferably 90 wt.% or more, particularly preferably 95 wt.% or more).

[0077] The weight ratio of the total amount of component (a) monosodium salt of foramsulfuron to the total amount of component (b) diluent or diluent mixture in a mixture according to the invention preferably corresponds to the weight ratios specified above (as preferred), in each case based on the total weight of the mixture, which are specified in connection with the manufacturing process of the crystal form B according to the invention.

[0078] The crystalline form B according to the invention can be used as such or in the form of agrochemical preparations (formulations) in combination with other pesticides, such as insecticides, acaricides, nematicides, herbicides, fungicides, safeners, fertilizers, and / or growth regulators, e.g., as a finished formulation or as tank mixes. The combination formulations can be produced based on the formulations mentioned below, taking into account the physical properties and stabilities of the active ingredients to be combined. The crystalline form B according to the invention can be formulated in various ways, generally using formulation aids commonly used in pesticides and / or other (agrochemical) active ingredients.

[0079] The invention therefore relates in a further aspect to an agrochemical preparation containing (a) a herbicidally effective amount of crystalline form B, and one or more further components selected from the group consisting of the following components (bi), (b-ii) and (b-iii): (bi) formulation aids commonly used in pesticides, (b-ii) further agrochemical active ingredients, and (b-iii) of crystalline form C.

[0080] Preferably, a formulation according to the invention contains as component (b-ii) preferably one or more safeners (preferably isoxadifen, isoxadifen ethyl, and / or cyprosulfamide) and / or one or more further herbicidal active ingredients.

[0081] The other herbicidal active substances are preferably selected from those listed in "The Pesticide Manual", 16th edition, The British Crop Protection Council and the Royal Society of Chemistry, 2012. The preferred additional herbicidal active substances are those mentioned in EP 0 790 771 A1 or EP 1 104 239 A1, in particular further ALS inhibitors (acetolactate synthase inhibitors), preferably thiencarbazone-methyl and its salts, and / or further sulfonylurea herbicides, preferably amidosulfuron, mesosulfuron, mesosulfuron-methyl, iodosulfuron, iodosulfuron-methyl, and their respective salts, such as iodosulfuron sodium or iodosulfuron-methyl sodium (the particular advantages regarding the (stability) improvement in combination with other sulfonylurea herbicides have already been explained at the outset).

[0082] In addition, the aforementioned agrochemical preparations (formulations) may contain the usual adhesives, wetting agents, dispersants, emulsifiers, penetrating agents, preservatives, antifreeze agents, solvents, fillers, carriers, colorants, defoamers, evaporation inhibitors, and agents that affect pH and viscosity. Examples of formulation aids are described, among other sources, in "Chemistry and Technology of Agrochemical Formulations", ed. D.A. Knowles, Kluwer Academic Publishers (1998).

[0083] Possible formulations for agrochemical preparations according to the invention containing the crystal form B according to the invention include, for example: spray powders (WP), water-soluble powders (SP), water-soluble concentrates, emulsifiable concentrates (EC), emulsions (EW), such as oil-in-water and water-in-oil emulsions, sprayable solutions, suspension concentrates (SC), oil- or water-based dispersions, oil-miscible solutions, capsule suspensions (CS), dusting agents (DP), seed dressings, granules for broadcast and soil application, granules (GR) in the form of micro-, spray-, lift- and adsorption granules, water-dispersible granules (WG), water-soluble granules (SG), ULV formulations, microcapsules and waxes.

[0084] Furthermore, it was found that in certain agrochemical preparations according to the invention, for example, some oil dispersions (OD), it is advantageous to include a mixture of crystal form B and crystal form C according to the invention. Such agrochemical preparations according to the invention are preferably based on formulations such as those described, for example, in US 2002 / 0016263 A1 or US 2005 / 0032647 A1.

[0085] Such agrochemical preparations containing a mixture of the inventive crystal form B and the inventive crystal form C showed further improved properties compared to otherwise identical formulations containing only crystal form B, for example, further improved storage stability, particularly with regard to the flowability and viscosity of the formulation.

[0086] In such agrochemical preparations according to the invention, the weight ratio of the total amount of crystal form B to the total amount of crystal form C is preferably in the range of 20 : 1 to 1 : 10, more preferably in the range of 10 : 1 to 1 : 5, more preferably in the range of 10 : 1 to 1 : 3, and particularly preferably in the range of 5 : 1 to 1 : 1, in each case based on the total weight of the agrochemical preparation according to the invention.

[0087] These individual formulation types are known in principle and are described, for example, in: Winnacker-Küchler, "Chemical Technology", Volume 7, C. Hanser Verlag Munich, 4th ed. 1986; Wade van Valkenburg, "Pesticide Formulations", Marcel Dekker, NY, 1973; K. Martens, "Spray Drying" Handbook, 3rd ed. 1979, G. Goodwin Ltd. London.

[0088] The necessary formulation aids, such as inert materials, surfactants, solvents, and other additives, are also known and are described, for example, in: Watkins, "Handbook of Insecticide Dust Diluents and Carriers", 2nd Ed., Darland Books, Caldwell NJ, Hv Olphen; "Introduction to Clay Colloid Chemistry"; 2nd Ed., J. Wiley & Sons, NY; C. Marsden, "Solvents Guide"; 2nd Ed., Interscience, NY 1963; McCutcheon's "Detergents and Emulsifiers Annual", MC Publ. Corp., Ridgewood NJ; Sisley and Wood, "Encyclopedia of Surface Active Agents", Chem. Publ. Co. Inc., NY 1964; Schönfeldt, "Interfacially Active Ethylene Oxide Adducts", Wiss. Verlagsgesellschaft, Stuttgart 1976; Winnacker-Küchler, "Chemical Technology", Volume 7, C. Hanser Verlag Munich, 4th edition 1986.

[0089] Spray powders are preparations that are uniformly dispersible in water and, in addition to the active ingredient, contain ionic and / or non-ionic surfactants (wetting agents, dispersants), such as polyoxyethylated alkylphenols, polyoxyethylated fatty alcohols, polyoxyethylated fatty amines, fatty alcohol polyglycol ether sulfates, alkanesulfonates, alkylbenzenesulfonates, sodium ligninsulfonate, 2,2'-dinaphthylmethane-6,6'-disulfonic acid sodium, sodium dibutylnaphthalenesulfonate, or sodium oleoylmethyltauric acid. To produce the spray powders, the herbicidal active ingredients are finely ground in conventional equipment such as hammer mills, blower mills, and air jet mills and simultaneously or subsequently mixed with the formulation aids.

[0090] Emulsifiable concentrates are produced by dissolving the active ingredient in an organic solvent, such as butanol, cyclohexanone, dimethylformamide, xylene, or higher-boiling aromatics or hydrocarbons, or mixtures of organic solvents, with the addition of one or more ionic and / or non-ionic surfactants (emulsifiers). Examples of emulsifiers include: alkylarylsulfonic acid calcium salts such as calcium dodecylbenzenesulfonate, or non-ionic emulsifiers such as fatty acid polyglycol esters, alkylaryl polyglycol ethers, fatty alcohol polyglycol ethers, propylene oxide-ethylene oxide condensation products, alkyl polyethers, sorbitan esters such as sorbitan fatty acid esters, or polyoxyethylene sorbitan esters such as polyoxyethylene sorbitan fatty acid esters.

[0091] Dusting agents are obtained by grinding the active ingredient with finely divided solid substances, e.g. talc, natural clays such as kaolin, bentonite and pyrophyllite, or diatomaceous earth.

[0092] Suspension concentrates can be water- or oil-based. They can be produced, for example, by wet milling using commercially available bead mills and, if necessary, the addition of surfactants, such as those already listed above for the other formulation types.

[0093] Emulsions, e.g. oil-in-water emulsions (EW), can be produced, for example, using stirrers, colloid mills and / or static mixers, with aqueous organic solvents and, if necessary, surfactants, such as those already listed above for the other formulation types.

[0094] Granules can be produced either by atomizing the active ingredient onto adsorbable, granulated inert material or by applying active ingredient concentrates to the surface of carrier materials such as sand, kaolinite, or granulated inert material using adhesives, e.g., polyvinyl alcohol, sodium polyacrylate, or mineral oils. Alternatively, suitable active ingredients can be granulated in the manner customary for the production of fertilizer granules – optionally in mixture with fertilizers.

[0095] Water-dispersible granules are typically produced using standard methods such as spray drying, fluidized bed granulation, disc granulation, mixing with high-speed mixers, and extrusion without solid inert material.

[0096] For the production of disc-shaped, fluidized bed, extruded and spray-dried granules, see, for example, the processes in "Spray-Drying Handbook" 3rd ed. 1979, G. Goodwin Ltd., London; J.E. Browning, "Agglomeration", Chemical and Engineering 1967, pages 147 ff; "Perry's Chemical Engineer's Handbook", 5th ed., McGraw-Hill, New York 1973, pp. 8-57.

[0097] Preferred agrochemical preparations according to the invention are those in which the crystal form B according to the invention is present in solid form. These are, for example, granules, encapsulated granules, tablets, water-dispersible granules, water-dispersible tablets, water-dispersible powders, dust formulations, formulations in which the active ingredient is present in dispersed form, such as: suspension concentrates (SC), oil-based suspension concentrates, suspoemulsions, or suspension concentrates.

[0098] Particularly preferred agrochemical preparations according to the invention containing the crystal form B according to the invention are those in which the agrochemical preparation is in a form selected from the group consisting of spray powders (WP), water-soluble powders (SP), suspension concentrates (SC), oil dispersions (OD), capsule suspensions (CS), dusting agents (DP), granules for spreading and soil application, granules (GR) in the form of micro-, spray-, lift- and adsorption granules, water-dispersible granules (WG), water-soluble granules (SG), ULV formulations, microcapsules and waxes.

[0099] For further details on the formulation of plant protection products, see, for example, GC Klingman, "Weed Control as a Science", John Wiley and Sons, Inc., New York, 1961, pages 81-96 and JD Freyer, SA Evans, "Weed Control Handbook", 5th Ed., Blackwell Scientific Publications, Oxford, 1968, pages 101-103.

[0100] The agrochemical preparations according to the invention generally contain 0.1 to 99 wt.%, in particular 0.1 to 95 wt.%, of the crystal form B according to the invention, based on the total weight of the agrochemical preparation, whereby the total amount of the crystal form B according to the invention may vary depending on the formulations.

[0101] In sprayable powders, the total amount of crystal form B according to the invention is typically 10 to 90 wt.%, the remainder up to 100 wt.% consists of usual formulation components.

[0102] In emulsifiable concentrates, the total amount of crystal form B according to the invention can be approximately 1 to 90 wt.%, preferably 5 to 80 wt.%. Powder-like formulations regularly contain a total amount of crystal form B according to the invention of 1 to 30 wt.%, preferably 5 to 20 wt.%. In water-dispersible granules, the total amount of crystal form B according to the invention is, for example, in the range of 1 to 95 wt.%, or in the range of 10 to 80 wt.%, based on the total weight of the agrochemical preparation.

[0103] The invention therefore also relates to a method for controlling harmful plants and / or for regulating plant growth, characterized in that an effective quantity of crystal form B, a composition containing crystal form B as defined above, or an agrochemical preparation according to the invention as defined above, applied to the plants, plant seeds, the soil in which or on which the plants grow, or the cultivation area.

[0104] Furthermore, it was found that the crystal form B, the mixtures, compositions, and formulations according to the invention, each as defined within the scope of the present invention, are suitable for controlling weeds or for regulating plant growth. The control of weeds or the regulation of plant growth is advantageously carried out in certain crops. Preferred crops are, in particular, rapeseed, soybeans, cotton, sugar beet, and grasses, especially maize, barley, wheat, rye, oats, triticale, millet, and rice, with maize being particularly preferred. In a preferred embodiment, the crops, especially those specified as preferred, are transgenic plants.

[0105] It can also be used on lawns, such as on golf courses. Examples:

[0106] The following examples illustrate the invention. Unless otherwise stated, all specifications refer to weight.

[0107] The symbol ">" means "greater than" and the symbol and "<" means "less than". Example 1: Production of crystal form A

[0108] 1000 g of N-[(4,6-Dimethoxypyridin-2-yl)-aminocarbonyl]-2-dimethylaminocarbonyl-5-formylamino-benzenesulfonamide were placed in 4750 g of 5 °C cold MeOH (6000 mL).

[0109] For this purpose, 32 g of seed crystals of crystal form A (according to EP 0 757 679 A1) were added and the mixture was cooled to 0 °C in 20 minutes. After reaching a temperature of 0 °C, 418 g (440 mL) of 30% sodium methylate solution were added within 2 hours, so that an internal temperature of 5 °C was not exceeded.

[0110] The resulting very pasty mixture was then distributed onto two refrigerated 4-liter frits and filtered by suction. After approximately 2 hours, the filtration was stopped and each frit was rinsed with 500 mL of water.

[0111] A total of 2220 g of the wet product were obtained, which were then dried at 65 °C under a pressure < 100 mbar. The drying process lasted a total of 44 hours. Drying was stopped when the methanol content reached 1.5 wt% residual, yielding 1012 g of a 97% product. Example 2: Variation of temperature during the production of crystal form A in methanol

[0112] In separate containers, 20 g of N-[(4,6-Dimethoxypyridin-2-yl)-aminocarbonyl]-2-dimethylaminocarbonyl-5-formylamino-benzenesulfonamide were placed in 100 g of MeOH.

[0113] One gram of seed crystals of crystal form A was added, and one equivalent of NaOMe as a 30% methanolic solution was added at the specified temperature over a period of two hours. The post-reaction time was three hours in each case.

[0114] To isolate the individual products, each mixture was heated or cooled to 20 °C and then filtered. After drying at 65 °C at a pressure < 100 mbar, the residual methanol content in each product was determined. Test No. T in °C Filtration time in seconds MeOH content in wt.% 1 0 150 0,53 2 15 50 1,49 3 35 4 2,83 4 50 5 5,19 Example 3: Storage of the methanol-moist crystal form A and its transformation into crystal form C

[0115] In separate containers, 5 g of crystal form A were stirred with 20 g of MeOH and then filtered.

[0116] The moistened products were stored at 20 °C, 30 °C, and 35 °C for one week, with a sample taken daily. These samples were dried at 65 °C and 100 mbar, and the respective methanol content was then determined.

[0117] After just 2 days (35 °C), 3 days (30 °C) and 7 days (20 °C) the crystal form A had practically completely transformed into the crystal form C (MeOH content approximately 6.4 wt.%). Example 4: Production of crystal form B from crystal form A

[0118] 1000 g of N-[(4,6-Dimethoxypyridin-2-yl)-aminocarbonyl]-2-dimethylaminocarbonyl-5-formylaminobenzenesulfonamide sodium salt (crystal form A) were suspended in 3000 g of acetone and heated under reflux for 2 hours. After cooling to 20 °C, the suspension was filtered. Filtration took 60 minutes.

[0119] The resulting wet product was then dried overnight at 70 °C and a pressure < 100 mbar. 9230 g of a 98.6% product were obtained. The MeOH content in this product was < 0.1 wt%, and the acetone content was < 0.05 wt%. Example 5: Production of crystal form B from crystal form C

[0120] 100 g of N-[(4,6-Dimethoxypyridin-2-yl)-aminocarbonyl]-2-dimethylaminocarbonyl-5-formylaminobenzenesulfonamide sodium salt (crystal form C; MeOH content approximately 6.4%) were suspended in 300 g of acetone and heated under reflux for 2 hours. After cooling to 20 °C, the suspension was filtered. Filtration took a few seconds.

[0121] The wet product was dried overnight at 70 °C and a pressure of < 100 mbar.

[0122] 92 g of a 99.2% pure product were obtained. The methanol content in this product was below the detection limit, and the acetone content was 0.026 wt.%. Example 6: Preparation of crystal form B from foramsulfuron and sodium methylate

[0123] 100 g of N-[(4,6-Dimethoxypyridin-2-yl)-aminocarbonyl]-2-dimethylaminocarbonyl-5-formylaminobenzenesulfonamide were suspended in 300 g of acetone and reacted with one equivalent of NaOMe as a 30% methanolic solution (40.21 g) over one hour at 40 °C. The resulting mixture was then heated under reflux for two hours. After cooling to 20 °C, the suspension was filtered. Filtration took approximately 30 seconds.

[0124] The wet product was dried overnight at 70 °C and a pressure of < 100 mbar.

[0125] 104 g of a 98.4% product were obtained. The methanol content of the obtained product was 0.006 wt%, and the acetone content was 0.048 wt%. Example 7: Preparation of crystal form B from foramsulfuron and sodium ethylate

[0126] 100 g of N-[(4,6-Dimethoxypyridin-2-yl)-aminocarbonyl]-2-dimethylaminocarbonyl-5-formylaminobenzenesulfonamide were suspended in 400 g of acetone and reacted under reflux for one hour with the equivalent of NaOEt as a 21% ethanolic solution (73.1 g). The mixture was then heated under reflux for a further two hours. After cooling to 20 °C, the suspension was filtered. Filtration took approximately 60 seconds.

[0127] The wet product was dried overnight at 70 °C and a pressure of < 100 mbar.

[0128] 102 g of a 98.6% product were obtained. The ethanol content of the obtained product was 0.0105 wt%, and the acetone content was 0.024 wt%. Example 8: Stability test of crystal form B in methanol

[0129] 10 g of crystal form B (MeOH content < 0.01%) were suspended in 100 g of methanol and stirred for 7 days at 30 °C. The mixture was then filtered and subsequently dried overnight at 70 °C and a pressure < 100 mbar.

[0130] 9.1 g of a 99.4% pure product were obtained. The methanol content of the obtained product was 0.004 wt%, and the acetone content was 0.0003 wt%. Example 9: Investigation of the chemical storage stability of crystal forms A and B

[0131] Crystal forms A and B were each incorporated separately into an otherwise identical formulation in the form of oil dispersions (OD) and stored under the same conditions.

[0132] The oil dispersions were stored under the following storage conditions and analyzed with regard to the chemical degradation of crystal form A and B: Storage for two weeks at 40°C (hereinafter referred to as 2W 40°C) Storage for four weeks at 40°C (hereinafter referred to as 4W 40°C) Storage for two weeks at 54°C (hereinafter referred to as 2W 54°C)

[0133] This also simulates storage over a longer period at a correspondingly lower temperature.

[0134] The crystal forms were incorporated into three different formulations in the form of oil dispersions (OD), these formulations containing, in addition to the agrochemical active ingredients listed below, common formulation components such as emulsifiers, thickeners, and diluents, as well as, in some cases, pH adjusters and / or defoamers.

[0135] Formulation OD1 contained, in addition to 3.05 wt% of crystal form A or B, the following active ingredients: 0.1 wt% iodosulfuron methyl sodium (a sulfonylurea herbicide) and 2.91 wt% isoxadifen ethyl (a safener).

[0136] In addition to 3.21 wt% of crystal form A or B, formulation OD2 contained as further active ingredients 1.02 wt% thiencarbazone methyl and 1.53 wt% cyprosulfamide (a safener).

[0137] In addition to 3.21 wt% of crystal form A or B, formulation OD3 contained the following active ingredients: 0.11 wt% iodosulfuron methyl sodium (a sulfonylurea herbicide), 1.02 wt% thiencarbazone methyl and 1.53 wt% cyprosulfamide (a safener). Table 9-1: Chemical stability of crystal forms A and B in formulation OD1 Crystal form Decrease in % 4W 40°C 2W 54°C Crystal form A 3,4 7,7 Crystal form B 1,5 3,4 Table 9-2: Chemical stability of crystal forms A and B in formulation OD2 Crystal form Decrease in % 2W 40°C 2W 54°C Crystal form A 1,8 8,6 Crystal form B 0,6 1,8 Table 9-3: Chemical stability of crystal forms A and B in formulation OD3 Crystal form Decrease in % 4W 40°C 2W 54°C Crystal form A 2,1 4,8 Crystal form B 0,3 1,4 Example 10: Preparation of crystal form B from foramsulfuron and sodium methylate

[0138] 100 g of N-[(4,6-Dimethoxypyridin-2-yl)-aminocarbonyl]-2-dimethylaminocarbonyl-5-formylaminobenzenesulfonamide were suspended in 300 g of a mixture of acetone / methanol (80:20 parts by weight) and treated with one equivalent of NaOMe as a 30% methanolic solution over two hours at 30 °C. The mixture was then stirred for another two hours at 30 °C. After cooling to 20 °C, the suspension was filtered for 50 seconds.

[0139] The wet product was dried overnight at 70 °C and a pressure of < 100 mbar.

[0140] 102 g of a 98.6% product were obtained. The methanol content of the obtained product was 0.03 wt%, and the acetone content was 0.014 wt%. Example 11: Preparation of crystal form B from foramsulfuron and sodium methylate

[0141] 100 g of N-[(4,6-Dimethoxypyridin-2-yl)-aminocarbonyl]-2-dimethylaminocarbonyl-5-formylaminobenzenesulfonamide were suspended in a mixture of 150 g acetone and 100 g methanol and heated to 30 °C. Over two hours, 38.6 g of NaOMe as a 30% methanolic solution were added at a constant rate. The mixture was then stirred for one hour at 30 °C. The temperature was then increased to 40 °C, and after one hour at this temperature, it was heated for another hour at 45 °C.

[0142] After cooling to 20 °C, the suspension was filtered, and the filter cake was washed with 100 g of acetone.

[0143] The wet product was dried overnight at 70 °C and a pressure of < 100 mbar.

[0144] The methanol content in the obtained product was 0.10 wt%, the acetone content was 0.13 wt%. Example 12: Sorption / desorption curve of crystal forms B

[0145] Sorption and desorption curves of crystal form B were measured isothermally at 25°C.

[0146] The sorption curve indicates the water absorption with increasing relative humidity, the desorption curve the drying behavior with moisture reduction. Relative humidity Sorption (wt%) Desorption (wt%) 10,0% 0,100 0,846 20,0% 0,201 1,227 30,0% 0,313 1,495 40,0% 0,444 1,760 50,0% 0,566 2,086 60,0% 0,684 2,269 70,0% 0,864 2,485 80,0% 1,085 3,016 90,0% 2,335 5,151

[0147] The test results show that crystal form B is not hygroscopic. Example 13: Investigation of the hygroscopy of crystal forms A, B and C

[0148] 100 mg each of crystal forms A, B, and C were separately filled into small snap-top vials. These three vials were placed, without caps, in a beaker whose bottom was covered with a small amount of water. The beaker was then sealed with a stretchable closure film and stored at 25 °C for one week. After this storage period, the water content of each sample was determined by Karl Fischer titration. The water content of the sample with crystal form B was 0.4 wt%, while the water content of the samples with crystal forms A and C was 15.7 wt% and 21.3 wt%, respectively.

[0149] The samples of crystal forms A and C were hygroscopic and very tough and sticky after storage, whereas the sample of crystal form B remained crystalline and powdery.

Claims

1. Monosodium salt of foramsulfuron in crystalline form, characterized in that the X-ray powder diffractogram of this salt using Cu Kα radiation at 25°C has at least 3 of the following 2Θ (2 theta) values: 28 (2 theta) values in °6.26.414.414.614.718.419.220.123.224.

72. Monosodium salt of foramsulfuron according to Claim 1, characterized in that the X-ray powder diffractogram of this salt using Cu Kα radiation at 25°C has at least 4, preferably at least 6, preferably at least 8, more preferably all of the 2Θ (2 theta) values specified in Claim 1.

3. Monosodium salt of foramsulfuron according to Claim 1, characterized in that the X-ray powder diffractogram of this salt using Cu Kα radiation at 25°C in addition has at least two, four, six, eight, ten, twelve or more of the following 2Θ (2 theta) values: 10.310.511.111.311.412.012.112.412.612.913.614.015.015.115.416.016.217.017.218.218.820.320.620.821.221.622.723.724.625.425.926.226.927.127.728.329.030.230.530.731.031.231.932.532.633.734.835.635.936.236.436.937.

44. Monosodium salt of foramsulfuron according to any of Claims 1 to 3, characterized in that the Raman spectrum thereof has at least the following bands: Band maximum [cm-1]295929151686158715266943451335. Composition comprising the monosodium salt of foramsulfuron according to any of Claims 1 to 4 in a total amount of at least 5% by weight, based on the total amount of monosodium salt of foramsulfuron present in the composition.

6. Composition according to Claim 5, wherein the composition is present in solid form at 25°C and 1013 mbar, and / or the content of monosodium salt of foramsulfuron is 80% by weight or more, based on the total weight of the composition.

7. Use of the monosodium salt of foramsulfuron according to any of Claims 1 to 4 or of a composition according to Claim 5 or 6 for preparing agrochemical formulations.

8. Monomethanol solvate of the monosodium salt of foramsulfuron in crystalline form, characterized in that the X-ray powder diffractogram of this salt using Cu Kα radiation at 25°C has at least 3 of the following 2Θ (2 theta) values: 2Θ (2 theta) values in °9.19.19.712.616.218.524.124.324.

69. Method for preparing the monosodium salt of foramsulfuron in crystalline form according to one or more of Claims 1 to 4, comprising the step of (a) suspending a monosodium salt of foramsulfuron, the monomethanol solvate of the monosodium salt of foramsulfuron according to Claim 8, or a mixture of these 2 crystal forms, in a diluent or diluent mixture, wherein the diluent or diluent mixture used in step (a) is selected from the group consisting of alcohols having 3 to 6 carbon atoms, in this case preferably primary alcohols having 3 to 6 carbon atoms, and ketones having 3 to 6 carbon atoms, and mixtures thereof, or comprises at least 20% by weight thereof.

10. Method for preparing the monosodium salt of foramsulfuron in crystalline form according to any of Claims 1 to 4, comprising the step of (a) suspending foramsulfuron in a diluent or diluent mixture, (b) reacting foramsulfuron with a base containing sodium, preferably an organic base, in this case preferably sodium methoxide and / or sodium ethoxide, wherein the diluent or diluent mixture used in step (a) is selected from the group consisting of alcohols having 3 to 6 carbon atoms, in this case preferably primary alcohols having 3 to 6 carbon atoms, and ketones having 3 to 6 carbon atoms, and mixtures thereof, or comprises at least 20% by weight thereof.

11. Method according to Claim 9 or 10, characterized in that the method is carried out at a temperature of at least 0°C.

12. Method according to any of Claims 9 to 11, characterized in that the ratio by weight of the total amount of foramsulfuron, monosodium salt of foramsulfuron, and monomethanol solvate of the monosodium salt of foramsulfuron according to Claim 8, to the total amount of diluent or diluent mixture used in step (a) is less than 2:1.

13. Mixture comprising (i) monosodium salt of foramsulfuron according to any of Claims 1 to 4 and / or a solvate thereof according to Claim 8, and (ii) a diluent or diluent mixture selected from the group consisting of alcohols having 3 to 6 carbon atoms, in this case preferably primary alcohols having 3 to 6 carbon atoms, and ketones having 3 to 6 carbon atoms, and mixtures thereof, or comprises at least 20% by weight thereof.

14. Agrochemical formulation comprising (a) a herbicidally effective amount of the monosodium salt of foramsulfuron in crystalline form according to any of Claims 1 to 4, and one or more further constituents selected from the group consisting of the following constituents (b-i), (b-ii) and (b-iii): (b-i) formulation auxiliaries customary in the pesticide field, (b-ii) further agrochemical active ingredients, and (b-iii) the monomethanol solvate of the monosodium salt of foramsulfuron according to Claim 8.

15. Method for controlling harmful plants or for regulating the growth of plants, characterized in that an effective amount - of the monosodium salt of foramsulfuron according to any of Claims 1 to 4, - a composition according to Claim 5 or 6, or - an agrochemical formulation according to Claim 14 is applied to the plants, seeds of plants, the soil in which or on which the plants grow or the area under cultivation.