CRYSTAL MODIFICATION OF PROPANIL

Abstract

The present invention relates to the crystalline modification of (3,4-dichlorophenyl)propanamide (propanil), to a process for preparing the same, to pesticide mixtures and compositions comprising the crystalline modification of (3,4-dichlorophenyl)propanamide, and to a method for weed control using the mixtures and compositions.

Description

CRYSTALLINE MODIFICATION OF PROPANYL ηΐτηαηη / ζζηζ / Ε / γίΛΐ TECHNICAL FIELD OF THE INVENTION The present invention relates to the crystalline modification of N-(3,4-dichlorophenyl)propanamide, to a process for preparing the crystalline modification, to pesticide combinations and compositions comprising the crystalline modification, and to a method for controlling weeds using the crystalline modification. BACKGROUND OF THE INVENTION N-(3,4-Dichlorophenyl)propanamide is a herbicide commonly known as propanil. Several processes for the preparation of propanil have been described. For example, patents GB903766, US3382280, GB1063528, CN1775745, and US3158650 describe detailed preparation procedures for propanil. Patent GB903766 relates to the preparation of propanil. Recrystallization of the final product was carried out using aqueous methanol. Patent GB903766 describes the melting point of propanil as 91 °C. US patent 3382280 describes the preparation as well as the recrystallization of propanil using cyclohexane. However, none of the above techniques mention that different crystalline forms have different shapes and physical properties. The characterization of propanil obtained by the processes described in the prior art is usually performed using analytical methods such as NMR and melting point determination. In the 13th edition of the Pesticide Manual, propanil is described as odorless, colorless crystals with a melting point of 91.5 °C. The melting points described in the prior art are in the range of 91 to 93 °C. The properties of different crystalline forms of a compound vary in many ways. Examples of such properties specific to certain forms of a compound include color, solubility, crystal size and shape, particle density, fluidity, melting point, thermal stability, and reactivity. For the large-scale manufacture and formulation of a commercial product such as propanil, which is available as flakes, it is crucial to know if different crystalline modifications of the compound exist or how they can be prepared and characterized. Such crystalline forms are highly relevant because they can lead to improved bioefficacy and, consequently, a reduction in pesticide dosage, which, in turn, has a direct and positive impact on the environment. Propanil is a widely used contact herbicide. It is one of the most commonly used herbicides in rice fields. It has been used at rates up to 5.0 kg / ha to control many broadleaf and grass weeds, including Amaranthus retroflexus, Digitaria spp., Echinochloa spp., Panicum spp., and Setaria spp. Large quantities of propanil are required for effective weed control, raising concerns about its effects on human health and the environment. Considering the large-scale use of propanil for effective post-emergence control of many broadleaf weeds, a reduction in its use may be a better choice to directly impact the hazardous and toxicological problems associated with prolonged use, which in turn will help to continue using this herbicide effectively. It has now been discovered that propanil exists in a different crystal form that has very advantageous properties such as improved bioefficacy. The description of the different crystalline modification of propanil, as well as the preparation procedure and characterization of any crystalline modification of propanil, is unknown to date. OBJECTIVES OF THE INVENTION Accordingly, an objective of the present invention is to provide a crystalline modification of propanil. Another objective of the present invention is to provide a process for the preparation of the crystalline modification of propanil. Another objective of the present invention is to prepare the crystalline modification of propanil in high yield and purity. Yet another objective of the present invention is to provide an economically viable process for the preparation of the crystalline modification of propanil. An objective of the present invention is to provide agrochemical combinations comprising the crystalline modification of propanil. Yet another objective of the present invention is to provide agrochemical compositions comprising the crystalline modification of propanil. Another objective of the present invention is to provide a process for preparing agrochemical compositions comprising the crystalline modification of propanil. Another objective of the present invention is to provide a method for weed control comprising agrochemical compositions comprising the crystalline modification of propanil. ηΐτηαηη / ζζηζ / Ε / γίΛΐ BRIEF DESCRIPTION OF THE INVENTION The present invention provides a crystalline modification of propanil. Furthermore, it relates to a process for the preparation of a crystalline modification of propanil. The present invention also relates to agrochemical compositions comprising a crystalline modification of propanil. The present invention further provides a process for preparing compositions comprising a crystalline modification of propanil. In addition, agrochemical combinations are provided comprising a crystalline modification of propanil with one or more pesticides. In addition, agrochemical compositions comprising a crystalline modification of propanil in conjunction with one or more different pesticides and a process for preparing such compositions are provided. In another aspect, a method is provided for using a crystalline modification of propanil to effectively control unwanted weed species. DETAILED DESCRIPTION OF THE INVENTION The inventors of the present invention surprisingly discovered that propanil exists in different crystalline forms. Accordingly, a crystalline modification of propanil and a process for preparing the crystalline modification are provided. Surprisingly, it has been observed that the crystalline morphology of propanil (technical sample) changes intensely with the variation of the polarity of the solvent in which the crystallization takes place. Therefore, crystalline propanil is provided. In addition, a process for preparing crystalline propanil is provided. More surprisingly, crystalline propanil has been observed to lead to increased bioefficacy. Accordingly, agrochemical compositions comprising crystalline propanil are provided. The inventors of the present invention further observed that agrochemical combinations comprising crystalline modification of propanil resulted in improved bioefficacy in controlling unwanted weed species. Accordingly, agrochemical combinations comprising crystalline propanil with one or more different pesticides are provided. ηΐτηαηη / ζζηζ / Ε / γίΛΐ In addition, a process is provided for the preparation of agrochemical compositions comprising crystalline modification of propanil. Accordingly, agrochemical compositions comprising crystalline modification of propanil in conjunction with one or more different pesticides are provided. In addition, a process is provided for preparing agrochemical compositions comprising crystalline modification of propanil in conjunction with one or more pesticides. As used in the present description, the phrase crystalline modification of propanil should be interpreted as the crystalline propanil of the present invention. In one aspect, the present invention provides a process for the preparation of crystalline propanil, said process comprising crystallizing propanil from a halogenated hydrocarbon solvent. In one embodiment, the process comprises crystallizing propanil from a solvent mixture comprising at least one halogenated hydrocarbon solvent and at least one second organic solvent. In one modality, the precise chemical procedure that can be used to crystallize propanil is not particularly limiting and can be carried out by an experienced technician according to the standard conventional procedure as long as the criticality of the selected solvent is maintained. In another embodiment, the crystalline modification of propanil according to the present invention was prepared by a process comprising the following steps: a) prepare a concentrated solution of propanil in a halogenated hydrocarbon solvent or in a mixture of a halogenated hydrocarbon solvent and one or more organic solvents; b) cool the solution; and c) carry out crystallization. In one embodiment of the present invention, the halogenated hydrocarbon solvent is selected from lower halogenated hydrocarbons with Ci to Ce carbon atoms. According to another modality, the halogenated hydrocarbon solvent is selected from the group consisting of dichloromethane, dichloropropane, trichloroethane, chloroform, and dichloroethane. In a preferred embodiment of the present invention, the halogenated hydrocarbon solvent is selected from dichloromethane or dichloroethane. In one embodiment of the present invention, the solvent is a mixture of halogenated hydrocarbon solvent and one or more organic solvents. ηΐτηαηη / ζζηζ / Ε / γίΛΐ In one embodiment of the present invention, the organic solvent is a non-polar organic solvent. In another embodiment of the present invention, the nonpolar organic solvent is selected from, but not limited to, aliphatic or aromatic hydrocarbon solvents or ether solvents. In a preferred embodiment of the present invention, the nonpolar organic solvent is selected from, but not limited to, pentane, cyclopentane, hexane, cyclohexane, heptane, octane, benzene, toluene, 1,4-dioxane, or diethyl ether. In one embodiment of the present invention, the temperature at which the concentrated propanil solution can be prepared ranges from approximately 30° to approximately 120°C. In one embodiment of the present invention, during step (b), the concentrated technical propanil solution is cooled to a temperature ranging from approximately 0°C to approximately 25°C. According to a preferred embodiment of the present invention, crystallization is carried out at a temperature ranging from approximately 0°C to approximately 15°C. The term "perform" in step (c) refers to stirring the solution to initiate crystallization. According to another preferred embodiment of the present invention, the crystals are insulated at a temperature ranging from approximately 0°C to approximately 15°C. According to a preferred embodiment of the present invention, the crystalline propanil was prepared by a process comprising the following steps: a) prepare a propanil solution in halogenated hydrocarbon solvent at a temperature in the range of approximately 30° to approximately 120°C; b) cool the mixture to a temperature in the range of approximately 0°C to approximately 25°C; and c) carry out crystallization at a temperature in the range of approximately 0 to approximately 15 °C. According to another preferred embodiment of the present invention, the crystalline propanil was prepared by a process comprising the following steps: a) prepare a propanil solution in a mixture of halogenated hydrocarbon solvent and at least one non-polar solvent at a temperature in the range of approximately 30° to approximately 120°C; b) cooling the mixture to a temperature in the range of about 0o to about 25°C; and ηΐτηαηη / ζζηζ / Ε / γίΛΐ c) carry out crystallization at a temperature in the range of approximately 0 to approximately 15 °C. In one modality, the prepared crystals are insulated by filtration. In one aspect, the present invention provides crystalline propanil. In a preferred embodiment, the present invention provides crystalline propanil prepared by a process comprising the following steps: a) prepare a concentrated solution of propanil in a halogenated hydrocarbon solvent or in a mixture of a halogenated hydrocarbon solvent and one or more organic solvents; b) cool the solution; and c) carry out crystallization. Crystalline propanil according to the present invention possesses a characteristic X-ray powder diffraction pattern, which is expressed, alternatively, in terms of the 2-Θ parameters and d spaces. In one modality, a crystalline modification of propanil is provided that exhibits an X-ray diffraction pattern with characteristic peaks expressed in 2θ(±0.2°) at at least three of the following positions: 12.51, 14.93, 17.11, 19.8, 21.35, 21.83, 22.91, 23.55, 24.91, 26.09, 29.27, 32.13, 31.07, 38.13 and 39.91. In another modality, a crystalline modification of propanil is provided that exhibits an X-ray diffraction pattern with characteristic peaks expressed at 20(±0.2°) at 12.51, 14.93, 17.11, 19.8, 21.35, 21.83, 22.91, 23.55, 24.91, 26.09, 29.27, 32.13, 31.07, 38.13 and 39.91. DESCRIPTION OF THE FIGURES Figure 1 illustrates an X-ray powder diffraction pattern of crystalline modification of propanil. Figure 2 illustrates X-ray diffraction studies of simple crystals showing two molecules in the asymmetric unit at PA1, i.e., in known crystalline form, and both molecules have the side chains on the same side. Figure 3 illustrates X-ray diffraction studies of single crystals showing two molecules in the asymmetric unit in crystalline modification of the present invention and the molecules are oriented in opposite directions. Figure 4 illustrates crystalline propanil comprising propanil crystals comprising two molecules in their asymmetric unit, said two molecules being conformationally oriented at an angle of approximately 65.2° with respect to each other around the C1-N1 bond. ηΐτηαηη / ζζηζ / Ε / γίΛΐ Figure 5a illustrates crystalline propanil comprising propanil crystals comprising two molecules in their asymmetric unit, said two molecules being conformationally oriented at an angle of approximately 65.2° with respect to each other around the C1-N1 bond. Figure 5b illustrates crystalline propanil comprising propanil crystals comprising two molecules in their asymmetric unit, said two molecules being conformationally oriented at an angle of approximately 65.2° with respect to each other around the C1-N1 bond. Figure 6 illustrates the superposition of the second molecule of crystalline propanil of the present invention against the conventionally known crystalline propanil which shows a different orientation of the side chain. In another embodiment, the present invention provides crystalline modified propanil characterized by the following X-ray powder diffraction pattern in terms of 2y d spaces: ηΐτηαηη / ζζηζ / Ε / γίΛΐ Table 1 d(A°) 20 7.064+0.Γ 12.51±0.2° 5.92±0.1° 14.93+0.2° 5.168+0.1° 17.11+0.2° 4.464+0.1° 19.87+0.2° 4.155+0.1° 21.35+0.2° 4.065±0.1° 21.83+0.2° 3.875±0.1° 22.91±0.2° 3.771±0.1° 23.55±0.2° 3.57±0.1° 24.91+0.2° 3.41±0.1° 26.09+0.2° 3.047+0.1° 29.27+0.2° 2.782+0.1° 32.13+0.2° 2.8742±0.1° 31.07+0.2° 2.363±0.1° 38.13±0.2° 2.258+0.1° 39.91±0.2° The crystalline modification of propanil according to the present invention has characteristic structural coordinates. Therefore, in another embodiment, the present invention provides a crystalline modification of propanil having the structure defined by the following structural coordinates: Table 2 Parameter Value Crystal system Monoclinic Space group P2i / ca 17.8853(2) A b 11.6179(1) A c 9.8524(9) A a 90.00° β 92.761(6)° Y 90.00° Volume 2044.8(3) A3 Z 4 Density (calculated) 1.417 g / cc ηΐτηαηη / ζζηζ / Ε / γίΛΐ Furthermore, propanil was re-crystallized from aqueous methanol (hereafter referred to as prior art 1 or PA1) according to the literature and compared to the crystalline modification according to the present invention. In this respect, the present invention provides a crystalline modification of propanil having a spatial orientation of molecules within the crystals as defined by Figure 3. In another aspect, the present invention provides a propanil crystal, said crystal comprising two molecules in its asymmetric unit, said molecules being oriented in opposite directions. In one embodiment, the present invention provides crystalline propanil, said crystalline propanil comprising propanil crystals comprising two molecules in their asymmetric unit, said molecules being oriented in opposite directions. In one embodiment, the present invention provides crystalline propanil, said crystalline propanil comprising propanil crystals comprising two molecules in their asymmetric unit, said molecules being oriented in opposite directions and having a spatial arrangement of atoms in one molecule arranged relative to the atoms in the second molecule defined by the following ORTEP shown in Figure 4. In one embodiment, the present invention provides crystalline propanil, said crystalline propanil comprising propanil crystals comprising two molecules in their asymmetric unit; said two molecules are conformationally oriented at an angle of approximately 65.2° with respect to each other around the C1-N1 bond. Without being subject to the theory, it is believed that the relative orientation around the C1-N1 bond between the two molecules in the asymmetric unit of crystalline propanil of the present invention occurs due to free conformational rotation around the C1-N1 bond. The spatial arrangement of atoms in the second molecule in crystalline propanil according to the present invention was compared with the spatial arrangement of atoms in conventionally known crystalline propanil and described in Figure 6. Thus, it was concluded that the crystalline propanil of the present invention differed from conventionally known crystalline propanil in the spatial orientation of the two molecules in the crystals relative to each other. Surprisingly, it was discovered that this spatial orientation of the two molecules relative to each other was the source of the significant increase in the herbicidal efficacy of the propanil crystals according to the present invention. In this context, the term crystalline modification of propanil according to the present invention defines and includes the crystalline modification of propanil having the characteristic spatial orientation of the molecules within the crystal as defined in any of the above-described modes or aspects, particularly with reference to: (a) the X-ray powder diffraction pattern described in Figure 1; or (b) the 2-Θ parameters and d spaces described in Table 1; or (c) the structural coordinates described in Table 2; or (d) the spatial orientation of molecules within the crystals defined by Figure 3; or (e) the spatial arrangement of atoms in one molecule relative to the atoms in the second molecule defined by the ORTEP view depicted in Figure 4; or (f) the two molecules in the asymmetric unit are conformationally oriented at an angle of approximately 65.2° relative to each other around the C1-N1 bond depicted in Figure 5(a); or (g) the two molecules are conformationally oriented at an angle of approximately 65.2° relative to each other around the C1-N1 bond defined by Figure 5(b); or (h) the comparative relative overlap of the second molecule against the conventional crystals represented in Figure 6. It is intended that all the foregoing descriptions of the relative spatial arrangement of molecules in the propanil crystals of the present invention describe, individually and in specific combinations with each other, the crystalline propanil of the present invention. Accordingly, references to crystalline propanil of the present invention may be understood as designating references to the crystalline propanil described in each of the aspects or embodiments mentioned above, both individually and in all conceivable combinations thereof. In another embodiment, the present invention relates to agrochemical compositions comprising crystalline propanil. In a preferred embodiment of the present invention, the agrochemical composition comprises from approximately 0.1% to approximately 100% by weight of the crystalline modification of propanil. According to another embodiment of the present invention, an agrochemical composition is provided comprising the crystalline modification of propanil in conjunction with other agronomically acceptable excipients. In another embodiment of the present invention, agrochemical combinations are provided comprising the crystalline modification of propanil in conjunction with one or more different pesticides. Other active ingredients that can be combined with the crystalline modification of propanil of the present invention are selected from pesticides such as herbicides, fungicides, and insecticides. In one embodiment, another active ingredient that can be combined with the crystalline modification of propanil of the present invention is selected from, but not limited to, an isoxazolidinone herbicide, a urea herbicide, a triazine herbicide, a hydroxybenzonitrile herbicide, a thiocarbamate herbicide, a pyridazine herbicide, chloroacetanilide herbicides; benzothiazole herbicides; carbanylate herbicides, cyclohexene oxime herbicides; picolinic acid herbicides; pyridine herbicides; quinolinecarboxylic acid herbicides; chlorotriazine herbicides, aryloxyphenoxypropionic herbicides, oxadiazolone herbicides; phenylurea herbicides, sulfonanilide herbicides, triazolopyrimidine herbicides, amide herbicides, pyridazine herbicides, dinitroaniline herbicides, or combinations thereof. In another embodiment of the present invention, another active ingredient that can be combined with the crystalline modification of propanil of the present invention is selected from an amide herbicide such as alidochlor, amicarbazone, beflubutamid, benzadox, benzipram, bromobutide, cafenstrol, ciprazol, dimethenamid, dimethenamid-P, difenamid, epronaz, etnipromid, fentrazamide, flucarbazone, flupoxam, fomesafen, halosafen, huangcaoling, isocarbamid, isoxaben, napropamide, napropamide-Mnaptalam, petoxamid, propizamide, quinonamid, saflufenacil, tebutam, thiafenacil, a sulfonamide herbicide such as asulam, carbasulam, fenasulam, oryzalin, penoxsulam, piroxsulam, oryloxycarboxylic acids such as MCPA-thioethyl, aryloxyphenoxypropionates such as ηΐτηαηη / ζζηζ / Ε / γίΛΐ clodinafop-propargyl, cyhalofop-butyl, diclofops, fluazifops, haloxyfops and its esters, haloxyfop-P and its esters, quizalofops, chloroacetamides such as acetolochlor, alachlor, butachlor, dimetenamid, metolachlor, propachlor,cyclohexanedione oximes such as aloxidim, butroxidim, clethodim, cloproxidim, cycloxidim, profoxidim, sethoxidim, tepraloxidim, tralcoxidim, benzamides such as isoxaben, benzoic acid derivatives such as dicamba, etofumesate, dinitroanilines such as benfluralin, butralin, chlornidine, dinitramine, dipropalin, ethalfluralin, fluchlorralin, isopropalin, metalpropalin, nitralin, oryzalin, pendimethalin, prodiamine, profluralin, trifluralin, diphenyl ethers such as acifluorfen, aclonifen, bifenox, clomethoxyfen, chlornitrofen, etnipromid, fluorodifen, fluoroglycofen, fluoronitrofen, fomesafen, fucaomi, furiloxyfen, halosafen, lactofen, nitrofen, nitrofluorfen, oxyfluorfen, organophosphate herbicides such as glufosinate and glyphosate, hydroxybenzonitriles such as bromoxynil, imidazolinones such as fenamidone, imazapic, imazamox, imazapic, imazapyr, imazethapyr, imazaquin, isoxazolidinones such as clomazone paraquat such as bipyridylium, phenyl carbamates such as desmedipham,fenmedifam, phenylpyrazoles such as pirafluphen-ethyl, phenylpyrazolines such as pinoxaden, pyridinecarboxylic acids or synthetic auxins such as picloram, clopyralid and triclopyr, pyrimidinyloxybenzoics such as bispyribac-sodium, sulfonylureas such as amidosulfuron, azimsulfuron, bensulfuron-methyl, chlorsulfuron, chlorimuron, cyclosulfamuron, ethoxysulfuron, flazasulfuron, flucetosulfuron, flupyrsulfuron, foramsulfuron, halosulfuron, imazosulfuron, mesosulfuron, metsulfuron-methyl, methiopyrisulfuron, monosulfuron, nicosulfuron, orthosulfamuron, oxasulfuron, primisulfuron, propirisulfuron, pyrazosulfuron, rimsulfuron, sulfometuron, sulfosulfuron, trifloxysulfuron, flazasulfuron, foramsulfuron, flupirsulfuron-methyl-sodium, nicosulfuron, rimsulfuron, sulfosulfuron, tribenuron-methyl, trifloxysulfuron-sodium, triflusulfuron, tritosulfuron, triazolopyrimidines such as penoxsulam, metosulam, florasulam, triketones such as mesotriones, sulcotrione, ureas such as diuron,linuron, phenoxycarboxylic acids such as 2,4-D, MCPA, MCPB, mecoprops and triazines such as atrazine, simazine and terbuthylazine. In another embodiment, another active ingredient that can be combined with the crystalline modification of propanil of the present invention is selected from, but not limited to, amide fungicides, acylamino acid fungicides, anilide fungicides, benzamide fungicides, sulfonamide fungicides, strobilurin fungicides, aromatic fungicides, benzimidazole fungicides, carbamate fungicides, carbanylate fungicides, conazole fungicides (imidazole triazoles), copper fungicides, dithiocarbamate fungicides, imidazole fungicides, organophosphate fungicides, oxazole fungicides, pyrazole fungicides, pyridine fungicides, or combinations thereof. According to another embodiment of the present invention, another active ingredient that can be combined with the crystalline propanil of the present invention is selected from, but not limited to, arsenic insecticides, botanical insecticides, carbamate insecticides, benzofuranyl methylcarbamate insecticides, dimethylcarbamate insecticides, oxime carbamate insecticides, phenyl methylcarbamate insecticides, diamide insecticides, dinitrophenol insecticides, fluorine insecticides, formamidine insecticides, fumigant insecticides, inorganic insecticides, insect growth regulators, benzoylphenylurea chitin synthesis inhibitors, macrocyclic lactone insecticides, neonicotinoid insecticides, and insecticide analogues of nereistoxin, organochlorine insecticides, organophosphate insecticides, organothiophosphate insecticides, heterocyclic organothiophosphate insecticides, phenyl organothiophosphate insecticides,Phosphonate insecticides, phosphonothiate insecticides, phosphoraamidate insecticides, phosphoramidothioate insecticides, phosphorodiamide insecticides, oxadiazine insecticides, oxadiazolone insecticides, phthalimide insecticides, physical insecticides, pyrazole insecticides, pyrethroid insecticides, pyrethroid ether insecticides, pyrimidamine insecticides, pyrrole insecticides, quaternary ammonium insecticides, sulfoximine insecticides, tetramic acid insecticides, tetronic acid insecticides, thiazole insecticides, thiazolidine insecticides, and thiourea insecticides. According to one embodiment of the present invention, an agrochemical composition comprising crystalline propanil in conjunction with other agronomically acceptable excipients is provided. In one embodiment of the present invention, the active ingredient added in conjunction with the propanil crystalline modification of the present invention is selected from phenoxyacetic acid herbicides such as 2-(4-chloro-2-methylphenoxy)acetic acid or 2,4-D. Accordingly, a composition comprising the propanil crystalline modification, 2-(4-chloro-2-methylphenoxy)acetic acid, and agronomically acceptable excipients is provided. The composition comprises from approximately 20% to approximately 99% by weight of the propanil crystalline modification and from approximately 0.1% to approximately 40% by weight of the phenoxyacetic acid herbicide. In another embodiment of the present invention, the active ingredient added in conjunction with the propanil crystalline modification of the present invention is selected from an isoxazolidinone herbicide such as clomazone. Accordingly, a composition comprising propanil crystalline modification, clomazone, and agronomically acceptable excipients is provided. The composition comprises from approximately 20% to approximately 99% by weight of the propanil crystalline modification and from approximately 0.1% to approximately 40% by weight of an isoxazolidinone herbicide. According to another embodiment of the present invention, the active ingredient added in conjunction with the propanil crystalline modification of the present invention is selected from pyridine herbicides such as triclopyr and its derivatives. Accordingly, a composition comprising the propanil crystalline modification, triclopyr, and agronomically acceptable excipients is provided. The composition comprises from approximately 20% to approximately 99% by weight of the propanil crystalline modification and from approximately 0.1% to approximately 40% by weight of a pyridine herbicide or its derivatives. In another embodiment of the present invention, the active ingredient added in conjunction with the propanil crystalline modification of the present invention is selected from sulfonylurea herbicides, such as halorulfuron, metsulfuron, or bensulfuron or their derivatives. Accordingly, a composition is provided comprising the propanil crystalline modification, halosulfuron, metsulfuron, or bensulfuron or their derivatives, and agronomically acceptable excipients. The composition comprises from approximately 20% to approximately 99% by weight of the propanil crystalline modification and from approximately 0.1% to approximately 40% by weight of a sulfonylurea herbicide or its derivative. In another embodiment of the present invention, the active ingredient added in conjunction with the propanil crystalline modification of the present invention is selected from sulfonamide herbicides such as penoxsulam. Accordingly, a composition comprising the propanil crystalline modification, penoxsulam, and agronomically acceptable excipients is provided. The composition comprises from approximately 20% to approximately 99% by weight of the propanil crystalline modification and from approximately 0.1% to approximately 40% by weight of a sulfonamide herbicide or its derivatives. In one embodiment, the herbicide that can be combined with a crystalline modification of propanil of the present invention is preferably selected from 2-(4-chloro-2-methylphenoxyacetic acid, clomazone, 2,4-D, triclopyr, halosulfuron, bensulfuron, metsulfuron-methyl, their derivatives and penoxsulam. The compositions comprising crystalline forms of the present invention include solid and liquid-based formulations such as powders, granules, dry formulations, solutions, emulsions, suspensions, and microencapsulations in polymeric substances. These formulations are produced in a known manner, for example, by mixing the crystalline forms with suitable formulation auxiliaries such as solvents / carriers, optionally with adjuvants such as surfactants, emulsifiers, dispersing agents, defoaming agents, antifreeze agents, colorants, wetting agents, anti-caking agents, biocides, viscosity modifiers, and binding agents. The compositional content of these adjuvants is not particularly limiting and can be determined by a skilled technician according to conventional protocols. In one embodiment of the present invention, the surfactants that can be added to the compositions are selected from non-ionic and / or anionic surfactants. Examples of non-ionic surfactants include alkylphenol alkoxylates, alcohol alkoxylates, fatty amine alkoxylates, polyoxyethylene glycerol fatty acid esters, castor oil alkoxylates, fatty acid alkoxylates, fatty amide alkoxylates, fatty polydiethanolamides, lanolin ethoxylates, fatty acid polyglycol esters, isotridecyl alcohol, fatty amides, methylcellulose, fatty acid esters, alkyl polyglycosides, glycerol fatty acid esters, polyethylene glycol, polypropylene glycol, polyethylene glycol / polypropylene glycol block copolymers, and alkyl polyethylene glycol ethers. alkyl polypropylene glycol ethers, polyethylene glycol / polypropylene glycol ether block copolymers (polyethylene oxide / polypropylene oxide block copolymers) and mixtures thereof.The preferred non-ionic surfactants are fatty alcohol ethoxylates, alkyl polyglycosides, fatty acid esters of glycerol, castor oil alkoxylates, fatty acid alkoxylates, fatty amide alkoxylates, lanolin ethoxylates, fatty acid polyglycol esters, and ethylene oxide / propylene oxide block copolymers and mixtures thereof. Examples of anionic surfactants include alkylyl sulfonates, phenyl sulfonates, alkyl sulfates, alkyl sulfonates, arylalkyl sulfonates, alkyl ether sulfates, alkylyl ether sulfates, alkyl polyglycol ether phosphates, polyaryl phenyl ether phosphates, alkyl sulfosuccinates, olefin sulfonates, paraffin sulfonates, petroleum sulfonates, taurides, sarcosides, fatty acid salts, alkylnaphthalenesulfonic acids, naphthalenesulfonic acids and lignosulfonic acids, condensates of sulfonated naphthalenes with formaldehyde or with formaldehyde and phenol, and, if applicable, urea, and further condensates of phenolsulfonic acid, formaldehyde and urea, lignosulfite waste liquors and lignosulfonates, alkyl phosphates, alkylyl phosphates, for example, tristyryl phosphates, and, furthermore, polycarboxylates, such as, for example, polyacrylates, maleic anhydride / olefin copolymers, including alkali metal, alkaline earth metal,Ammonium and amine salts of the aforementioned substances and mixtures thereof. The preferred anionic surfactants are those containing at least one sultanate group, and particularly its alkali metal and its ammonium salts and mixtures thereof. In one embodiment of the present invention, suitable solvents for use in the compositions of the present invention include water, aromatic solvents (e.g., Solvesso products, xylene, mix-xylene), alcohols (e.g., methanol, butanol, pentanol, benzyl alcohol), ketones (e.g., cyclohexanone, gamma-butyrolactone), pyrrolidones (NMP, NOP), ketone solvents, glycols, acetates (glycol diacetate), carbonates such as propylene carbonates, fatty acid dimethylamides (e.g., N,N-dimethyl octanamide, N,N-dimethyl decanamide, Hallcomid), fatty acid esters of rhodiasolv and amino carboxylic acid esters (polarclean). In principle, solvent mixtures may also be used. In one embodiment, the compositions of the present invention comprise a crystallization inhibitor that is commonly used for this purpose in agrochemical compositions. In one embodiment of the present invention, the compositions comprise a rheology modifier (or a viscosity-modifying additive or a structuring agent). ηΐτηαηη / ζζηζ / Ε / γίΛΐ Suitable compounds are those commonly used for this purpose in agrochemical formulations. Examples include bentonites, attapulgites, and polysaccharides such as xanthan gum and kelzan gum. In another embodiment of the present invention, the compositions comprise antifreeze agents. Suitable antifreeze agents are liquid polyols, for example, ethylene glycol, propylene glycol, or glycerol. Common surfactants present in agrochemical active ingredient formulations are suitable for use as emulsifiers. Examples include ethoxylated nonylphenols, polyethylene glycol ethers of linear alcohols, conversion products of alkylphenols with ethylene oxide and / or propylene oxide, ethylene oxide-propylene oxide block copolymers, polyethylene glycols and polypropylene glycols (PC Emulsogen), fatty acid esters, alkyl sulfonates, alkyl sulfates, aryl sulfates, ethoxylated arylalkylphenols such as tristyryl-phenol ethoxylate, ethoxylated and propoxylated arylalkylphenols, and sulfated or phosphated arylalkylphenol ethoxylates or ethoxy- and propoxylates. In another embodiment of the present invention, the compositions comprise dispersing agents. All substances commonly used as dispersing agents in plant protection products are suitable for this purpose.The preferred dispersants are of anionic or non-ionic nature and are selected, for example, from polyethylene glycol / polypropylene glycol block copolymers, polyethylene glycol alkyl ethers, polypropylene glycol alkyl ethers, polyethylene glycol / polypropylene glycol ether block copolymers, alkyl phosphates, for example, tristyril phosphates, lignosulfonic acids, sulfonated naphthalene condensates with formaldehyde or with formaldehyde and phenol and, if suitable, urea and, furthermore, phenolsulfonic acid, formaldehyde and urea condensates, lignosulfite and lignosulfonate waste liquors, polycarboxylates, such as, for example, polyacrylates, maleic anhydride / olefin copolymers including alkali metal salts, alkaline earth metal salts, ammonium and amine from the substances mentioned above. In another embodiment of the present invention, the compositions comprise wetting agents. The preferred wetting agents are anionic or nonionic in nature and are selected, for example, from naphthalenesulfonic acids, including their alkali metal, alkaline earth metal, ammonium, and amine salts, fatty alcohol ethoxylates, alkyl polyglycosides, fatty acid esters of glycerol, castor oil alkoxylates, fatty acid alkoxylates, fatty amide alkoxylates, fatty polydiethanolamides, lanolin ethoxylates, and polyglycol fatty acid esters. In one embodiment of the present invention, the compositions comprise a humectant selected from polyols such as sucrose, glycerin or glycerol, triethylene glycol, tripropylene glycol and propylene glycol. ηΐτηαηη / ζζηζ / Ε / γίΛΐ In one embodiment, a process is provided for preparing compositions comprising crystalline propanil and agronomically acceptable excipients. The process for preparing the compositions is not particularly restrictive. Accordingly, in a preferred embodiment, a process is provided for preparing compositions comprising crystalline propanil and agronomically acceptable excipients; said process comprises: a) mix the crystalline modification of propanil with usual agronomically acceptable excipients; b) add one or more pesticides if required; c) grind or pulverize if required; and d) granulate said mixture to obtain granular compositions. In one embodiment of the present invention, the process of adding the ingredients and / or other pesticides can be in any order. In another embodiment of the present invention, the granulation step is not particularly limiting. Suitable granulation processes include all conventional processes described in granulation technology, for example, spray drying, fluidized bed granulation, agglomeration, tray granulation, and particularly, extrusion granulation. In a preferred embodiment, a process is provided for preparing compositions comprising crystalline propanil, said process comprising the steps of: a) prepare a suspension of crystalline propanil; b) add other usual excipients; c) add one or more different pesticides if required; and d) grind the suspension to a desired particle size using appropriate equipment. In one embodiment of the present invention, the suspension preparation step and the suspension grinding step are not particularly limiting. In one embodiment of the present invention, the process of adding the ingredients can have any order. In a preferred embodiment, a process is provided for the preparation of compositions comprising crystalline propanil; said process comprises the steps of: a) prepare a solution of crystalline propanil in suitable solvents; b) add one or more different pesticides if required c) add other usual excipients such as emulsifiers; and d) Stir the mixture as required. ηΐτηαηη / ζζηζ / Ε / γίΛΐ In one embodiment of the present invention, the step of preparing a crystalline modification solution of propanil and the step of homogenizing the mixture are not particularly limiting. In one embodiment of the present invention, the process of adding the ingredients can have any order. The crystalline modification of propanil of the present invention is suitable for weed control. Accordingly, a method for weed control is provided comprising contacting weeds or their locus with an herbicide-effective amount of the crystalline modification of propanil. The crystalline modification of propanil of the present invention is suitable as a broad-spectrum herbicide for controlling / killing different types of broadleaf weeds, grasses, and rushes. Accordingly, a method is provided for controlling unwanted plants or for influencing plant growth by treating such plants in the field with an effective amount of a herbicidal composition comprising crystalline modification of propanil. In another embodiment of the present invention, a method is provided for controlling unwanted plants or for influencing plant growth by treating such plants or their locus in the field with an effective amount of a herbicidal composition comprising a combination of crystalline propanil with one or more active agrochemical ingredients. In another aspect, the present invention provides a method for controlling weeds by applying crystalline propanil or a composition thereof. In one modality, the method involves administering crystalline propanil in conjunction with one or more different pesticides. In one modality, the pesticide(s) can be selected from: (a) herbicides selected from an isoxazolidinone herbicide, a urea herbicide, a triazine herbicide, a hydroxybenzonitrile herbicide, a thiocarbamate herbicide, a pyridazine herbicide, chloroacetanilide herbicides; benzothiazole herbicides; carbanilate herbicides, cyclohexene oxime herbicides; picolinic acid herbicides; pyridine herbicides; quinolinecarboxylic acid herbicides; chlorotriazine herbicides, aryloxyphenoxypropionic herbicides, oxadiazolone herbicides; phenylurea herbicides, sulfonanilide herbicides, triazolopyrimidine herbicides, amide herbicides, pyridazine herbicides, dinitroaniline herbicides or combinations thereof; (b) fungicides selected from amide fungicides, acylamino acid fungicides, anilide fungicides, benzamide fungicides, sulfonamide fungicides, strobilurin fungicides, aromatic fungicides, benzimidazole fungicides, carbamate fungicides, carbanilate fungicides, conazole fungicides (imidazole triazoles), copper fungicides, dithiocarbamate fungicides, imidazole fungicides, organophosphorus fungicides, oxazole fungicides, pyrazole fungicides, pyridine fungicides or combinations thereof; and (c) insecticides selected from arsenic insecticides, botanical insecticides, carbamate insecticides, benzofuranyl methylcarbamate insecticides, dimethylcarbamate insecticides, insecticides, dinitrophenol insecticides, fluorine insecticides, formamidine insecticides, fumigant insecticides, inorganic insecticides, insect growth regulators, benzoylphenylurea chitin synthesis inhibitors,macrocyclic lactone insecticides, neonicotinoid insecticides, nereistoxin analogue insecticides, organochlorine insecticides, organophosphate insecticides, organothiophosphate insecticides, heterocyclic organothiophosphate insecticides, phenyl organothiophosphate insecticides, phosphonate insecticides, forfonothioate insecticides, phosphoramidate insecticides, phosphoramidothioate insecticides, phosphorodiamide insecticides, oxadiazine insecticides, oxadiazolone insecticides, phthalimide insecticides, physical insecticides, pyrazole insecticides, pyrethroid insecticides, pyrethroid ether insecticides, pyrimidinamine insecticides, pyrrole insecticides, quaternary ammonium insecticides, sulfoximine insecticides, tetramic acid insecticides, acid insecticides tetronic, tlazol insecticides, thiazolidine insecticides, and thiourea insecticides. The composition according to the present invention can also be prepared by tank-mixing the active ingredient with auxiliaries suitable for the formulation of these active ingredients or, alternatively, it can be sold as a kit of parts containing actives and other ingredients that can be mixed before spraying. Accordingly, in one embodiment, the present invention provides a multi-container agrochemical product comprising: a) a first container containing the crystalline modification of propanyl b) a second container containing other agrochemical adjuvants / surfactants / solvents and c) an instruction manual that teaches the user how to mix said ingredients before application Accordingly, in another embodiment, the present invention provides a multi-packaged agrochemical product comprising: ηΐτηαηη / ζζηζ / Ε / γίΛΐ a) a first container containing the crystalline modification of propanyl b) a second container containing other agrochemical adjuvants / surfactants / solvents c) optionally, a third container containing one or more different pesticides; and d) an instruction manual that teaches the user how to mix said ingredients before application. The methods of applying pesticide compositions and pesticide mixtures according to the present invention are not particularly limiting. It can be the simultaneous application of a premix or tank mix of active ingredients with suitable formulation auxiliaries, or it can be a sequential application of one after the other. The invention will now be described with reference to the following specific examples. It should be noted that the examples below illustrate rather than limit the invention, and that persons skilled in the art will be able to devise many alternative embodiments without departing from the scope of the invention. The preparation of propanil crystals using methanol as a solvent (prior technique 1 or PA1) according to patent GB903766 has been reproduced here for comparison with the crystalline modification of propanil of the present invention. Example 1; Preparation of the crystalline modification of propanil of the present invention by crystallization of dichloromethane: Technical propanil was obtained from the market. 497.7 mL of dichloromethane were charged into a glass kettle and 700 g of technical grade propanil were added while stirring at 25 °C. The suspension was stirred and heated to 38–40 °C until the propanil was completely dissolved, resulting in a clear solution. The solution was then slowly cooled to approximately 28–30 °C while stirring. The mass was further cooled to approximately 510 °C while stirring. The mass was stirred at 5–10 °C for 1 hour and filtered at 5–10 °C. The crystals were dried under vacuum at 20–25 °C to yield 579 g (82.7% yield, 99.7% by GC) of product. Example 2: Preparation of the crystalline modification of propanil according to the present invention by crystallization of a mixture of dichloromethane and hexane 100 mL of dichloromethane were placed in a glass kettle and 100 g of technical-grade propanyl was added while stirring at 25 °C. The mixture was heated to 50 °C while stirring and 200 mL of n-hexane was slowly added. The solution was stirred at 50 °C for one hour and then allowed to cool slowly to 10–15 °C and held at that temperature for one hour. The crystals were filtered at 10–15 °C. The crystals were dried under vacuum to obtain 95 g of product. Example 3: Large-scale preparation of the crystalline modification of propanil of the present invention by crystallization of dichloromethane 4679 grams of dichloromethane were loaded into a glass kettle. 5000 grams of propanil were added, followed by stirring and heating of the mixture to approximately 45 °C until the propanil was completely dissolved in the solvent, yielding a pale yellow to pale brown solution. The reaction mixture was cooled under stirring to approximately 30 °C in about 3–4 hours. The suspension was further cooled under stirring to approximately 10 °C and held at that temperature for about 1 hour. The suspension was filtered and washed using dichloromethane cooled to approximately 10 °C. The crystals were dried under vacuum at approximately 55–60 °C to obtain 3945 grams (79%) of the crystalline product. Example 4: A dry formulation comprising the crystalline modification of propanil was prepared according to the present invention as follows: ηΐτηαηη / ζζηζ / Ε / γίΛΐ Ingredients Quantity (% w / w) crystalline propanil 62.5 sodium alkylnaphthalenesulfonate, formaldehyde condensate 7.36 sodium docusate 0.96 sodium lignosulfonate 4.09 precipitated silica 1.58 kaolin (QS) 23.51 The composition was prepared as follows: The required amount of crystalline modification of propanil was mixed with the required amount of sodium alkylnatenesulfonate formaldehyde condensate, sodium docusate, sodium lignosulfonate, precipitated silica, and kaolin. Sufficient water was added to form a paste of the composition. The paste was then granulated using an extrusion granulation process to prepare granules. The granules were then dried. Example 5: A dry formulation comprising the crystalline modification of propanil was prepared according to the present invention as follows ηΐτηαηη / ζζηζ / Ε / γίΛΐ Ingredients Quantity (% w / w) crystalline propanil 82.00 mixture of anionic and non-ionic surfactants 7.5 sodium lignosulfonate 4.0 precipitated silica 1.2 antifoam 0.5 alkylnaphthalene sulfonate 4.0 kaolin (QS) 1.5 Example 6: A granular formulation comprising the crystalline modification of propanil and 4-chloro-2-methylphenylacetic acid was prepared according to the present invention as follows: Ingredients Quantity (% w / w) crystalline propanil 60.00 potassium polycarboxylate 7.36 sodium alkyl sulfate 3.50 modified sodium lignosulfonate 4.00 precipitated silica 1.58 4-chloro-2-methylphenylacetic acid 7.5 kaolin (QS) 16.06 Example 7: A granular formulation comprising the crystalline modification of propanil and methyl bensulfuron was prepared according to the present invention as follows: Ingredients Quantity (% w / w) crystalline propanil 62.5 sodium alkylnaphthalenesulfonate, formaldehyde condensate 7.36 sodium docusate 0.96 sodium lignosulfonate 4.09 precipitated silica 1.58 methyl bensulfuron 0.5 kaolin (QS) 23.01 Example 8: A granular formulation comprising the crystalline modification of propanil and metsulfuron-methyl was prepared according to the present invention as follows ηΐτηαηη / ζζηζ / E / γίΛΐ Ingredients Quantity (% w / w) crystalline propanil 62.5 sodium alkylnaphthalenesulfonate, formaldehyde condensate 7.36 sodium docusate 0.96 sodium lignosulfonate 4.09 precipitated silica 1.58 metsulfuron-methyl 0.5 kaolin (QS) 23.01 Example 9: A granular formulation comprising the crystalline modification of propanil and methyl halosulfuron was prepared according to the present invention as follows: Ingredients Quantity (% w / w) crystalline propanil 62.5 sodium alkylnaphthalenesulfonate, formaldehyde condensate 7.36 sodium docusate 0.96 sodium lignosulfonate 4.09 precipitated silica 1.58 methyl halosulfuron 0.5 kaolin (QS) 23.01 Example 10: A suspension concentrate comprising the crystalline modification of propanil and methyl bensulfuron was prepared according to the present invention as follows: Ingredients Quantity (% w / w) crystalline propanil 41.52 methyl bensulfuron 0.33 sulfated alkylarylphenol ethoxylate derivative 3.00 EOPO copolymer 1.75 alkylnaphthalene sulfonate formaldehyde copolymer 3.00 biocide 0.01 glycol 7.00 silica 0.50 antifoam 0.50 structuring agent 12.00 water q.s. ηΐτηαηη / ζζηζ / Ε / γίΛΐ The composition was prepared as follows: The required amount of water was added to the suspension preparation vessel. The required amount of alkylarylphenolethoxylate sulfate derivative, EOPO copolymer, and alkylnaphthalene sulfonate formaldehyde copolymer was added to the vessel while stirring, followed by the other excipients. Stirring continued until the solution was homogenized. The required amount of propanil and benzulfuron-methyl was added to the solution to form a uniform suspension, followed by milling to obtain the desired particle size. Example 11: A crystalline modification of propanil suspension concentrate was prepared as follows: Ingredients Quantity (% w / w) crystalline propanyl 41.61 sulfated alkylarylphenolethoxylate derivative 2.50 EOPO copolymer 1.50 alkylnaphthalene sulfonate formaldehyde copolymer 2.50 biocide 0.08 glycol 8.00 silica 0.50 antifoam 0.50 structuring agent 0.21 water q.s. Example 12: An emulsifiable concentrate of crystalline modification of propanil and clomazone was prepared as follows: Ingredient Amount % w / w crystalline propanil 42.00 clomazone 10.63 emulsifier PC 10.125 atlox 3418 04.575 rhodiasolv adma 10 20.00 mix-xylene (QS) 12.67 ηΐτηαηη / ζζηζ / Ε / γίΛΐ The composition was prepared as follows: The required amount of solvent mix-xylene and rhodiasolv adma 10 was loaded into the container followed by the addition of the required amount of propanil while stirring. Stirring continued until the propanil was completely dissolved. The required amount of clomazone was then added while stirring to obtain a homogenized solution. The required amount of Emulsogen PC and Atlox 3418 was added and stirred to obtain an emulsifiable concentrate. Example 13: An emulsifiable concentrate of crystalline modification of propanyl v triclopyr butyl ester was prepared as follows: Ingredients Quantity (% w / w) crystalline propanyl 35.91 triclopyr butyl ester 5.42 EOPO copolymer 1.01 aryl amine sulfonate 15.00 aromatic hydrocarbon solvent q.s. Field tests: Protocol: Field trials were conducted using the crystalline modified propanil compositions prepared according to the present invention as the broad-spectrum herbicide. The composition was optionally mixed with other tank-mixing aids and applied at an application rate of 1–2 kg / ha to cultivated and uncultivated land containing broadleaf weeds, grasses, and rushes. The dosage of the conventional commercial propanil formulation (Spada 60) is 4.0 kg / ha. Observations from 7 to 22 days after treatment are summarized in the tables below and demonstrate the bioefficacy of the compositions. Field trial 1: Study of weed control in rice fields using formulations comprising the crystalline modification of propanil A formulation comprising crystal modification of propanyl, (Example 4) a formulation comprising propanyl recrystallized from aqueous methanol according to the literature (previous technique 1 or PA1) as well as propanil market sample (Propanil 60 DF, Spada 60) for the same dosage as well as for a dosage higher than 4.0 kg / ha were tested in terms of weed control in paddy field. Weeds include Ischaemun rugosum, Leptochloa filiformie, Echinochloa colonum, Jussiaea linifolia and Cyperus ferax. ηΐτηαηη / ζζηζ / Ε / γίΛΐ Table 4: % of weed control 15 days after application Index product kg / ha Grass Echinochloa colonum ischaemun rugosum Leptochloa sp. Broad spectrum Jussiaea linifolia Cyperus ferax Eg.4 2 95 90 95 95 95 90 95 Spade 60 2 75 75 80 75 80 80 85 PA1 2 80 70 80 90 85 85 90 Spade 60 4 95 95 95 95 80 80 95 Table 5: % of weed control 22 days after application Product index kg / ha Gramínea Echinochloa colonum Ischaemun rugosum Leptochloa sp. Broad spectrum Jussiaea linifolia Cyperus ferax Ej-4 2 95 95 95 95 95 95 95 Spada 60 2 85 85 85 85 85 90 85 PA1 90 90 98 100 From the results presented above, it was observed that formulations comprising crystalline propanil prepared according to Example 4 showed good weed control at a lower application rate of 2 kg / ha. It was also noted that at any given application rate, formulations comprising the crystalline modification of propanil showed greater bioefficacy and consistency compared to Spada 60 (Propanil 60 DF, commercial sample). More specifically, it was observed that formulations comprising the crystalline modification of propanil exhibited better bioefficacy at a much lower application rate of 2.0 kg / ha than Spada 60 at an application rate of 4.0 kg / ha, which, in turn, resulted in effective herbicide use at a lower dosage.Thus, it was concluded that formulations comprising crystalline propanil can be effectively used as a broad-spectrum herbicide at a lower dosage with improved bioefficacy compared to other conventional propanil-based formulations. It was further observed that the crystalline propanil formulations according to the present invention demonstrated superior weed control against all weeds and appeared to be twice as biologically active as the conventional market sample. Field trial 2: Study of weed control in rice fields using a combination of crystalline modification of propanil and bensulfuron methyl. A combination of crystalline propanil and methyl bensulfuron (Example 10) was tested against a conventional mixture of propanil and methyl bensulfuron (Propadax) for weed control in rice fields containing numerous broadleaf weeds, grasses, and rushes. The mixture was tested at different dosages to study the efficacy of the combinations. Weeds in the field included Echinochloa colona, ​​Eleusine indica, Paspalum boscianum, Senna obtusifolia, Eclipta alba, Ipomoea triloba, Cyperus rotundas, and Cyperus iria. Observations from 5 to 7 days after treatment are summarized in the tables below and demonstrate the bioefficacy of the combinations according to the present invention. Table 6: % weed control 5 days after application ηΐτηαηη / ζζηζ / E / γίΛΐ Treatments broadleaf grasses rushes Example 10 (25%) 98 99 86.5 Propadax (25%) 92.5 91.5 60 Table 7: % weed control 7 days after application Treatments for broadleaf grasses and rushes Example 10 (50%) 90.5 89.5 91 Propadax (50%) 84 74.5 73 Example 10 (25%) 92 98 72.5 Propadax (25%) 87.5 82.5 40 It has been observed that the combination according to the present invention, comprising crystalline propanil and bensulfuron-methyl, provided better weed control compared to the conventional mixture. It has been noted that at lower dosages of approximately 50% and approximately 25%, the combination according to the present invention resulted in acceptable weed control compared to conventional mixtures. The mixture according to the present invention is found to be more bioeffective against various types of grasses, broadleaf weeds, and rushes. Furthermore, it was confirmed that the crystalline modification of the present invention exhibits improved bioefficacy and is effective at lower dosages compared to conventional propanil-based compositions.

Claims

1. A crystalline propanil characterized by at least one of the following properties: (a) the 20 parameters and d spaces described in the following table: d(A°) 20 7.064±0.Γ 12.51+0.2° 5.92+0.1° 14.93+0.2° 5.168±0.1° 17.11+0.2° 4.464±0.1° 19.87+0.2° 4.155±0.1° 21.35±0.2° 4.065±0.1° 21.83±0.2° 3.875±0.1° 22.91±0.2° 3.771±0.1° 23.55±0.2° 3.57+0.1° 24.91+0.2° 3.41+0.1° 26.09+0.2° 3.047±0.1° 29.27+0.2° 2.782±0.1° 32.13±0.2° 2.8742±0.1° 31.07±0.2° 2.363±0.1° 38.13±0.2° 2.258±0.1° 39.91+0.2° or (b) the structural coordinates described in the following table: Parameter Value Crystal system Monoclinic Space group P2i / ca 17.8853(2) A b 11.6179(1) A c 9.8524(9) A at 90.00° β 92.761(6)° Y 90.00° Volume 2044.8(3) A3 Z 4 Density (calculated) 1.417 g / cc 2. The crystalline propanil according to claim 1, wherein said crystalline propanil exhibits an X-ray diffraction pattern having characteristic peaks expressed at 20(±0.2°) in at least three of the following positions: 12.51, 14.93, 17.11, 19.8, 21.35, 21.83, 22.91, 23.55, 24.91, 26.09, 29.27, 32.13, 31.07, 38.13 and 39.

91.

3. The crystalline propanil according to claim 1, wherein said crystalline propanil exhibits an X-ray diffraction pattern having characteristic peaks expressed at 20 (±0.2°) at 12.51, 14.93, 17.11, 19.8, 21.35, 21.83, 22.91, 23.55, 24.91, 26.09, 29.27, 32.13, 31.07, 38.13 and 39.

91.

4. The crystalline propanil according to claim 1, comprising propanil crystals having two molecules in their asymmetric unit, said molecules being oriented in opposite directions.

5. The crystalline propanil according to claim 1, comprising propanil crystals having two molecules in their asymmetric unit, said two molecules being conformationally oriented at an angle of approximately 65.2° with respect to each other around the C1-N1 bond.

6. The crystalline propanil according to claim 1, characterized in that it is crystallized from a halogenated hydrocarbon solvent.

7. The crystalline propanil according to claim 6, wherein said halogenated hydrocarbon solvent is selected from lower halogenated hydrocarbons of Ci to Ce carbon atoms.

8. The crystalline propanil according to claim 6, wherein said halogenated hydrocarbon solvent is selected from the group consisting of dichloromethane, dichloropropane, trichloroethane, chloroform and dichloroethane.

9. The crystalline propanil according to claim 1, characterized in that it is crystallized from a mixture of halogenated hydrocarbon solvent and one or more organic solvents.

10. The crystalline propanil according to claim 9, wherein said organic solvent is a nonpolar organic solvent.

11. The crystalline propanil according to claim 10, wherein said nonpolar organic solvent is selected from aliphatic or aromatic hydrocarbon solvents or other solvents.

12. The crystalline propanil according to claim 11, wherein said nonpolar organic solvent is selected from pentane, cyclopentane, hexane, cyclohexane, heptane, octane, benzene, toluene, 1,4-dioxane or diethyl ether.