A benzoylpyrazole compound and its application

Abstract

The present invention discloses a benzoylpyrazole compound and its application, wherein the compound is shown in general formula I: the definitions of the substituents in general formula I are shown in the specification. The compound of general formula I of the present invention has excellent herbicidal activity and can be used for preventing and controlling agricultural weeds.

Description

Technical Field

[0001] The present invention belongs to the field of herbicides, and specifically relates to a benzoylpyrazole compound and its application. Background Art

[0002] Due to the succession and change of weed populations and the emergence and rapid development of resistance to chemical pesticides, people are increasingly aware of the need to protect the ecological environment, and are paying more and more attention to the pollution of chemical pesticides, the impact of pesticides on non-target organisms, and the fate of pesticides in the ecological environment. With the gradual reduction of cultivated land in the world, the continuous growth of population and the increase in demand for food, people are forced to rapidly develop agricultural production technology, improve and perfect farming systems, and need to continuously invent new and improved herbicidal compounds and compositions.

[0003] CN101573035A reported that certain benzoylpyrazole compounds have herbicidal activity, such as compound No. 4 (KC):

[0004]

[0005] The benzoylpyrazole compounds shown in the present invention have not been disclosed. Summary of the invention

[0006] The purpose of the present invention is to provide a benzoylpyrazole compound which is novel in structure and safe for crops and application thereof.

[0007] To achieve the above object, the technical solution of the present invention is as follows:

[0008] A benzoylpyrazole compound, the compound is shown in general formula I:

[0009]

[0010] Where:

[0011] X1 is selected from cyano, nitro, halogen, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 haloalkoxy, C1-C6 alkylthio, C1-C6 alkyl sulfoxide, C1-C6 alkylsulfonyl, C1-C6 alkoxy C1-C3 alkyl or C1-C6 alkoxy C1-C3 alkoxy C1-C3 alkyl;

[0012] X2 is selected from cyano, nitro, halogen, C1-C6 alkylthio, C1-C6 alkylsulfoxide, C1-C6 alkylsulfonyl or C1-C6 haloalkyl;

[0013] n is selected from 1 or 2;

[0014] R1 is selected from C1-C6 alkyl, C1-C6 haloalkyl, C3-C6 cycloalkyl, C3-C6 halocycloalkyl or C3-C6 cycloalkylC1-C3 alkyl;

[0015] R2 is selected from hydrogen, C1-C6 alkyl, C1-C6 haloalkyl, C3-C6 cycloalkyl or C3-C6 cycloalkylC1-C6 alkyl;

[0016] R3 is selected from hydrogen, C1-C6 alkyl, C1-C6 haloalkyl, C3-C6 cycloalkyl, C3-C6 halocycloalkyl, C3-C6 cycloalkylC1-C3 alkyl, C2-C6 alkenyl, C2-C6 alkynyl, C1-C6 alkylcarbonyl, C1-C6 haloalkylcarbonyl, C1-C6 alkoxycarbonyloxyC1-C6 alkyl, C1-C6 alkylsulfonyl, cinnamoyl, 5-7 membered alicyclic acyl containing 1-4 heteroatoms or 5-7 membered aromatic heterocyclic acyl containing 1-4 heteroatoms, and the hydrogen on the cinnamoyl, alicyclic acyl and aromatic heterocyclic acyl may be substituted by one or more of the following substituents, and the substituents are selected from nitro, halogen, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 haloalkoxy or C3-C6 cycloalkyl.

[0017] The preferred compound has the general formula I:

[0018] X1 is selected from halogen, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkylsulfonyl, C1-C6 alkoxy C1-C3 alkyl or C1-C6 alkoxy C1-C3 alkoxy C1-C3 alkyl;

[0019] X2 is selected from halogen, C1-C6 alkylsulfonyl or C1-C6 haloalkyl;

[0020] n is selected from 1 or 2;

[0021] R1 is selected from C1-C6 alkyl or C3-C6 cycloalkylC1-C3 alkyl;

[0022] R2 is selected from hydrogen, C1-C6 alkyl, C1-C6 haloalkyl, C3-C6 cycloalkyl or C3-C6 cycloalkylC1-C6 alkyl;

[0023] R3 is selected from hydrogen, C1-C6 alkylcarbonyl, C1-C6 alkoxycarbonyloxyC1-C6 alkyl, cinnamoyl or pyrazoloyl, and the hydrogen on the cinnamoyl and pyrazoloyl groups may be substituted by one or more of the following substituents, the substituents being selected from nitro, halogen, C1-C6 alkyl, C1-C6 haloalkyl, C1-C6 alkoxy, C1-C6 haloalkoxy or C3-C6 cycloalkyl.

[0024] The further preferred compounds are those having the general formula I:

[0025] X1 is selected from halogen, C1-C6 alkyl, C1-C6 haloalkyl or C1-C6 alkylsulfonyl;

[0026] X2 is selected from C1-C6 alkylsulfonyl or C1-C6 haloalkyl;

[0027] n is selected from 1 or 2;

[0028] R1 is selected from C1-C6 alkyl;

[0029] R2 is selected from hydrogen, C1-C6 alkyl or C3-C6 cycloalkyl;

[0030] R3 is selected from hydrogen, C1-C6 alkylcarbonyl, cinnamoyl or pyrazoloyl, and the hydrogen on the cinnamoyl and pyrazoloyl may be substituted by one or more of the following substituents, and the substituents are selected from C1-C6 alkyl or C1-C6 haloalkyl.

[0031] The further preferred compounds are those having the general formula I:

[0032] X1 is selected from chlorine or methyl;

[0033] X2 is selected from methylsulfonyl;

[0034] n is selected from 2;

[0035] R1 is selected from C1-C3 alkyl;

[0036] R2 is selected from hydrogen, methyl or cyclopropyl;

[0037] R3 is selected from hydrogen, C1-C3 alkylcarbonyl, cinnamoyl or pyrazoloyl, and the hydrogen on the cinnamoyl and pyrazoloyl may be substituted by one or more of the following substituents, and the substituents are selected from C1-C3 alkyl or C1-C3 haloalkyl.

[0038] In the definition of compounds of general formula I given above, the terms used are collectively defined as follows:

[0039] Alkyl refers to a straight chain or branched chain form, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl and other groups. Cycloalkyl refers to a cyclic chain form, such as cyclopropyl, methylcyclopropyl, cyclopropylcyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl and other groups. Alkenyl refers to a straight chain or branched chain alkenyl, such as 1-propenyl, 2-propenyl, butenyl, pentenyl and hexenyl and other groups. Alkyl refers to a straight chain or branched chain alkynyl, such as 1-propynyl, 2-propynyl, butynyl, pentynyl and hexynyl and other groups. Alkoxy refers to a group with an oxygen atom attached to the end of the alkyl group, such as methoxy, ethoxy, n-propoxy, isopropoxy, tert-butoxy and the like. A 5-7 membered aliphatic heterocycle containing 1-4 heteroatoms refers to a 5-7 membered heterocyclic compound containing 1-4 heteroatoms without aromatic characteristics, such as tetrahydrofuran, imidazolinone, caprolactam, etc. A 5-7 membered aromatic heterocycle containing 1-4 heteroatoms refers to a 5-7 membered heterocyclic compound containing 1-4 heteroatoms with aromatic characteristics, such as furan, thiophene, pyrazole, pyridine, etc.

[0040] The general formula compound I of the present invention can be prepared by the following method:

[0041]

[0042] The compound of general formula II is reacted with the compound of general formula III in a suitable solvent at a temperature ranging from -10°C to the boiling point of the suitable solvent for 0.5-48 hours to obtain the target compound I.

[0043] Suitable solvents are selected from dichloromethane, 1,2-dichloroethane, chloroform, carbon tetrachloride, hexane, benzene, toluene, ethyl acetate, acetonitrile, acetic acid, tetrahydrofuran, dioxane, N,N-dimethylformamide or dimethyl sulfoxide.

[0044] Adding a suitable alkaline substance is beneficial to the reaction. Suitable bases are selected from organic bases such as triethylamine, N,N-dimethylaniline or pyridine, or inorganic bases such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium bicarbonate, potassium carbonate, sodium methoxide, sodium tert-butoxide or potassium tert-butoxide.

[0045] The compound of formula III is commercially available or can be prepared from the corresponding acid, which is commercially available or prepared by referring to the operation in WO2009123714.

[0046] The preparation method of the compound of formula II is as follows:

[0047]

[0048] In the above formula, the general formula IV is reacted in a suitable solvent at a temperature of -10°C to the boiling point of a suitable solvent for 0.5-48 hours under the action of a base and a catalyst to obtain a compound of the general formula II; the suitable solvent is selected from dichloromethane, 1,2-dichloroethane, chloroform, carbon tetrachloride, hexane, benzene, toluene, ethyl acetate, acetonitrile, acetic acid, tetrahydrofuran, dioxane, N,N-dimethylformamide or dimethyl sulfoxide, etc. The suitable base is selected from sodium carbonate, potassium carbonate or triethylamine, etc. The suitable catalyst is selected from sodium carbonate, potassium carbonate, acetone cyanohydrin, azide, quaternary ammonium azide, metal cyanide or DMAP, etc.

[0049] The preparation method of the compound of formula IV is as follows:

[0050]

[0051] The compound of formula V is reacted with the compound of formula VI (available commercially or prepared by the method described in reference document EP0240001) in a suitable solvent at a temperature of -10°C to the boiling point of the suitable solvent for 0.5-24 hours to obtain the compound of formula IV. The suitable solvent is selected from dichloromethane, 1,2-dichloroethane, chloroform, carbon tetrachloride, hexane, benzene, toluene, ethyl acetate, acetonitrile, acetic acid, tetrahydrofuran, dioxane, N,N-dimethylformamide or dimethyl sulfoxide.

[0052] Adding a suitable alkaline substance is beneficial to the reaction. Suitable bases are selected from organic bases such as triethylamine, N,N-dimethylaniline or pyridine, or inorganic bases such as sodium hydroxide, potassium hydroxide, sodium carbonate, sodium bicarbonate, potassium carbonate, sodium methoxide, sodium tert-butoxide or potassium tert-butoxide.

[0053] The raw material carboxylic acid corresponding to the compound of general formula V (available commercially or prepared by the method described in reference documents CN86101277A or CN101573035A) reacts with an acyl halide reagent in a suitable solvent at a temperature of -10°C to the boiling point of the suitable solvent for 0.5-48 hours to obtain the compound of general formula V. The acyl halide reagent is selected from oxalyl chloride, thionyl chloride, phosphorus oxychloride, phosphorus trichloride or phosphorus pentachloride, etc. The suitable solvent is selected from dichloromethane, 1,2-dichloroethane, hexane, benzene, toluene, acetonitrile, acetic acid, dioxane or a liquid acyl halide reagent, etc.

[0054] The compound of general formula I of the present invention has herbicidal activity and can be used to control various weeds in agriculture.

[0055] The present invention also includes a herbicidal composition with the compound of general formula I as an active component. The weight percentage of the active component in the herbicidal composition is 1-99%. The herbicidal composition also includes an agriculturally acceptable carrier.

[0056] The herbicidal composition of the present invention can be applied in the form of a variety of formulations. The compound of the present invention is usually dissolved or dispersed in a carrier to prepare a formulation so that it is easier to disperse when used as a herbicide. For example, these chemical formulations can be made into wettable powders or emulsifiable concentrates. Therefore, in these compositions, at least one liquid or solid carrier is added, and it is usually necessary to add a suitable surfactant.

[0057] The present invention also provides a method for controlling weeds, which comprises applying a herbicidal effective amount of the herbicidal composition of the present invention to the weeds or the surface of the site where the weeds grow or the growth medium thereof. A more suitable effective dose is 1 gram to 1000 grams per hectare, and a preferred effective dose is 10 grams to 500 grams per hectare. For some applications, one or more other herbicides may be added to the herbicidal composition of the present invention, thereby producing additional advantages and effects.

[0058] The compounds of the present invention can be used alone or in admixture with other known insecticides, fungicides, plant growth regulators or fertilizers.

[0059] It should be understood that various changes and modifications can be made within the scope of the present invention as defined by the claims.

[0060] The advantages of the present invention are:

[0061] Compared with known benzoylpyrazole compounds, the benzene ring part of the general formula compound of the present invention contains an alkylsulfone methoxy substitution and has a novel structure. In addition, the benzoylpyrazole compound of the present invention has unexpectedly high herbicidal activity and also has high herbicidal activity at a lower dosage. It is not only highly effective, but also reduces the amount of pesticide used and the cost. It is also safe for crops and reduces pollution to the environment. DETAILED DESCRIPTION

[0062] The following examples and biological test results can be used to further illustrate the present invention, but are not intended to limit the present invention.

[0063] Synthesis Example

[0064] Example 1, Synthesis of Compound 26:

[0065] (1) Synthesis of methyl 2-methyl-3-methylthiomethoxy-4-methylsulfonylbenzoate

[0066]

[0067] Add methyl 2-methyl-3-hydroxy-4-methylsulfonylbenzoate (10 g, 41 mmol), DMF (50 ml), potassium carbonate (6.9 g, 50 mmol) to the reaction flask, and dropwise add chloromethyl methyl sulfide (4 g, 41 mmol). React at 60°C for 2 hours, add ethyl acetate (200 ml) and water (100 ml) to the reaction solution for separation and extraction, wash the organic phase with saturated brine (50 ml) in turn, dry over anhydrous magnesium sulfate, evaporate the solvent under reduced pressure, separate the residue by column chromatography, and obtain 10 g of yellow oil with a yield of 80%.

[0068] (2) Synthesis of methyl 2-methyl-3-methylsulfonemethoxy-4-methylsulfonebenzoate

[0069]

[0070] To the reaction flask, add methyl 2-methyl-3-methylthiomethoxy-4-methylsulfonylbenzoate (10 g, 32.9 mmol), acetic acid (30 ml), sodium tungstate (1 g, 3.3 mmol), heat to 60°C, slowly add 30% hydrogen peroxide (11.2 g, 99 mmol), keep warm for 1 hour, add water (100 ml) under ice bath and stir for 1 hour, solid precipitates, filter and dry to obtain 9 g of white solid, yield 81%.

[0071] (3) Synthesis of 2-methyl-3-methylsulfonemethoxy-4-methylsulfonebenzoic acid

[0072]

[0073] To the reaction flask, methyl 2-methyl-3-methylsulfonylmethoxy-4-methylsulfonylbenzoate (9 g, 26.8 mmol), ethanol (30 ml), and 10% aqueous sodium hydroxide solution (13 g, 32 mmol) were added. The mixture was reacted at room temperature for 2 hours. The solvent was removed, and water (50 ml) was added. The pH was adjusted to 2-3 with 10% dilute hydrochloric acid under ice bath. Solid precipitated and was filtered and dried to obtain 8.2 g of white solid. The yield was 95%.

[0074] (4) Synthesis of 2-methyl-3-methylsulfonemethoxy-4-methylsulfonebenzoyl chloride

[0075]

[0076] To the reaction flask, add 2-methyl-3-methylsulfonylmethoxy-4-methylsulfonylbenzoic acid (1.2 g, 3.7 mmol) and toluene (10 ml), and slowly add thionyl chloride (1.33 g, 11.2 mmol). The mixture is heated at reflux for 4 hours, and the solvent is evaporated under reduced pressure to obtain 1.2 g of a yellow oil, which is used directly in the next step.

[0077] (5) Synthesis of 4-(2-methyl-3-methylsulfonemethoxy-4-methylsulfonebenzoyl)-1,3-dimethyl-5-hydroxypyrazole

[0078]

[0079] Add 1,3-dimethyl-5-hydroxypyrazole (0.4 g, 3.7 mmol), dichloromethane (20 ml), triethylamine (0.6 g, 5.6 mmol) to the reaction flask, and dropwise add the dichloromethane solution (10 ml) of 2-methyl-3-methylsulfonylmethoxy-4-methylsulfonylbenzoyl chloride. Stir at room temperature for 2 hours, add triethylamine (0.6 g, 5.6 mmol) and 1 drop of acetone cyanohydrin, stir at room temperature overnight, add water (50 ml) and stir for half an hour, adjust the aqueous phase to pH = 2-3 with 10% dilute hydrochloric acid, solid precipitates, filter and dry to obtain 0.37 g of yellow solid, purity 95%, yield 24%.

[0080] Example 2. Synthesis of Compound 28

[0081] (1) Synthesis of 1-ethyl-5-methyl-3-pyrazolecarbonyl chloride

[0082]

[0083] To the reaction flask, 1-ethyl-5-methyl-3-pyrazolecarboxylic acid (0.2 g, 1.3 mmol) and toluene (10 ml) were added, and thionyl chloride (0.4 g, 3.3 mmol) was slowly added. The mixture was heated under reflux for 4 hours, and the solvent was evaporated under reduced pressure to obtain 0.22 g of a yellow oil, which was directly used for the next step.

[0084] (2) Synthesis of Compound 28

[0085]

[0086] 4-(2-methyl-3-methylsulfonylmethoxy-4-methylsulfonylbenzoyl)-1,3-dimethyl-5-hydroxypyrazole (0.5 g, 1.2 mmol), dichloromethane (10 ml), triethylamine (0.33 g, 3.3 mmol) were added to the reaction flask, and the dichloromethane solution (5 ml) of 1-ethyl-5-methyl-3-pyrazolecarbonyl chloride was added dropwise. Stir at room temperature for 1 hour, evaporate the solvent under reduced pressure, add ethyl acetate (100 ml) and water (50 ml) to the residue for separation and extraction, wash the organic phase with saturated brine (50 ml) in turn, dry over anhydrous magnesium sulfate, evaporate the solvent under reduced pressure, and separate the residue by column chromatography to obtain 0.15 g of white oil with a purity of 96% and a yield of 23%.

[0087] Example 3. Synthesis of Compound 12

[0088]

[0089] 4-(2-methyl-3-methylsulfonylmethoxy-4-methylsulfonylbenzoyl)-1-ethyl-5-hydroxypyrazole (0.5 g, 1.2 mmol), dichloromethane (10 ml), triethylamine (0.33 g, 3.3 mmol), and cinnamoyl chloride (0.18 g, 1.2 mmol) were added to the reaction flask. The mixture was stirred at room temperature for 1 hour, and the solvent was evaporated under reduced pressure. Ethyl acetate (100 ml) and water (50 ml) were added to the residue for separation and extraction. The organic phase was washed with saturated brine (50 ml) in turn, dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was separated by column chromatography to obtain 0.53 g of yellow oil with a purity of 90% and a yield of 80%.

[0090] By replacing the starting materials according to the above-described method, other compounds of general formula I can be obtained. Some compounds of general formula I are shown in Table 1.

[0091]

[0092] Table 1 Structures and physical properties of some compounds of general formula I

[0093]

[0094]

[0095]

[0096]

[0097]

[0098] Some compounds 1 H NMR (300MHz, CDCl3) data are as follows:

[0099] Compound 1: 7.79 (d, 1H), 7.41 (d, 1H), 7.33 (s, 1H), 5.16 (s, 2H), 3.54 (s, 3H), 3.41 (s, 3H), 3.24 (s, 3H), 2.30 (s, 3H).

[0100] Compound 3: 8.00 (s, 1H), 7.75 (d, 1H), 7.32 (d, 1H), 6.37 (s, 1H), 4.70 (s, 2H), 4.19 (q, 2H), 3.72 (s, 3H), 3.14 (s, 3H), 3.09 (s, 3H), 2.32 (s, 3H), 2.29 (s, 3H), 1.44 (t, 3H).

[0101] Compound 5: 7.89 (d, 1H), 7.81 (d, 1H), 7.71 (s, 1H), 7.58 (d, 2H), 7.46 (m, 3H), 7.39 (d, 1H), 6.41 (d, 1H), 4.90 (s, 2H), 3.75 (s, 3H), 3.09 (s, 3H), 3.06 (s, 3H), 2.39 (s, 3H).

[0102] Compound 7: 7.81 (d, 1H), 7.43 (d, 1H), 7.34 (s, 1H), 5.16 (s, 2H), 3.92 (q, 2H), 3.41 (s, 3H), 3.24 (s, 3H), 2.31 (s, 3H), 1.27 (t, 3H).

[0103] Compound 10: 8.01 (s, 1H), 7.74 (d, 1H), 7.31 (d, 1H), 6.37 (s, 1H), 4.70 (s, 2H), 4.18 (q, 2H), 4.01 (q, 2H), 3.13 (s, 3H), 3.08 (s, 3H), 2.32 (s, 3H), 2.29 (s, 3H), 1.44 (t, 3H), 1.42 (t, 3H).

[0104] Compound 11: 7.89 (d, 1H), 7.68 (s, 1H), 7.41 (d, 1H), 6.74 (s, 1H), 4.86 (s, 2H), 4.49 (q, 2H), 4.11 (q, 2H), 3.17 (s, 3H), 3.13 (s, 3H), 2.38 (s, 3H), 2.33 (s, 3H), 1.47 (t, 3H), 1.42 (t, 3H).

[0105] Compound 12: 7.89 (d, 1H), 7.82 (d, 1H), 7.71 (s, 1H), 7.56 (d, 2H), 7.45 (m, 3H), 7.38 (d, 1H), 6.43 (d, 1H), 4.89 (s, 2H), 4.07 (q, 2H), 3.09 (s, 3H), 3.07 (s, 3H), 2.39 (s, 3H), 1.46 (t, 3H).

[0106] Compound 26: 7.96 (d, 1H), 7.31 (d, 1H), 4.98 (s, 2H), 3.65 (s, 3H), 3.26 (s, 3H), 3.16 (s, 3H), 2.39 (s, 3H), 1.71 (s, 3H).

[0107] Compound 28: 7.71 (d, 1H), 7.27 (d, 1H), 6.25 (s, 1H), 4.61 (s, 2H), 4.17 (q, 2H), 3.61 (s, 3H), 3.10 (s, 3H), 3.07 (s, 3H), 2.57 (s, 3H), 2.31 (s, 3H), 2.25 (s, 3H), 1.42 (t, 3H).

[0108] Compound 37: 7.96 (d, 1H), 7.32 (d, 1H), 4.98 (s, 2H), 3.66 (s, 3H), 3.75 (s, 3H), 3.17 (s, 3H), 2.40 (s, 3H), 2.02 (q, 2H), 0.91 (t, 3H).

[0109] Compound 39: 7.71 (d, 1H), 7.27 (d, 1H), 6.24 (s, 1H), 4.62 (s, 2H), 4.17 (q, 2H), 3.62 (s, 3H), 3.11 (s, 3H), 3.07 (s, 3H), 3.02 (q, 2H), 2.31 (s, 3H), 2.25 (s, 3H), 1.43 (t, 3H), 1.34 (t, 3H).

[0110] Compound 40: 7.77 (d, 1H), 7.25 (d, 1H), 6.31 (s, 1H), 4.63 (s, 2H), 4.37 (q, 2H), 3.67 (s, 3H), 3.08 (s, 3H), 2.98 (s, 3H), 2.91 (q, 2H), 2.32 (s, 3H), 2.26 (s, 3H), 1.35 (t, 3H), 1.29 (t, 3H).

[0111] Compound 41: 7.83 (d, 1H), 7.54 (d, 1H), 7.45 (m, 5H), 7.29 (d, 1H), 5.99 (d, 1H), 4.79 (s, 2H), 3.62 (s, 3H), 3.01 (s, 3H), 2.93 (q, 2H), 2.82 (s, 3H), 2.35 (s, 3H), 1.30 (t, 3H).

[0112] Biotest Examples

[0113] Example 4: Determination of herbicidal activity

[0114] Sow the seeds of broadleaf weeds (zinnia, velvetleaf) or grass weeds (dogtail) in paper cups with a diameter of 7 cm filled with nutrient soil, cover with 1 cm of soil after sowing, suppress and water, and cultivate in the greenhouse according to the conventional method. Spray the stems and leaves after the weeds reach 2-3 leaves.

[0115] The compounds recorded in the above table were dissolved in acetone as the original drug, and then the test solution of the required concentration was prepared by standing tap water with 1‰ Tween 80 according to the test requirements. According to the designed dosage of the test, the spray treatment (spray pressure 1.95kg / cm 2 , spray volume 500L / hm 2 , crawler speed 1.48km / h). The test was repeated 3 times. After the test materials were treated, they were placed in the operation hall. After the liquid was naturally dried in the shade, they were placed in the greenhouse and managed according to the conventional method. The reaction of the weeds to the agent was observed and recorded. After treatment, the control effect of the test agent on the weeds was visually inspected regularly, and expressed as 0-100%, with "0" representing no control effect and "100%" representing complete kill.

[0116] The test results show that the compounds of general formula I generally have high control effects on a variety of weeds. Among some of the tested compounds, such as compounds 1, 3, 5, 7, 10, 11, 12, 26, 28, 37 and 39, the application dose is 600 g ai / hm 2 It has good control effect on zinnia, ramie and foxtail, with a control effect greater than or equal to 70%.

[0117] According to the above test method, some compounds of general formula I and KC were selected for activity test against zinnia. The results are shown in Table 2.

[0118] Table 2: Activity of some compounds of general formula I and control compound KC against zinnia (post-emergence, control effect %)

[0119]

[0120] According to the above test method, some compounds of general formula I and KC were selected for activity test on controlling velvetleaf. The results are shown in Table 3.

[0121] Table 3: Activity of some compounds of general formula I and reference compound KC against velvetleaf (post-emergence, control effect %)

[0122]

[0123] According to the above test method, some compounds of general formula I were selected and KC were tested for their activity against golden dogtail. The results are shown in Table 4.

[0124] Table 4: Activity of some compounds of general formula I and control compound KC against golden foxtail (post-emergence, control effect %)

[0125]

Claims

1. A benzoylpyrazole compound, characterized in that: The compound is shown in the general formula I Where: X1 is selected from C1-C6 alkyl, C1-C6 haloalkyl; X2 is selected from C1-C6 alkylsulfonyl; n is selected from 1 or 2; R1 is selected from C1-C6 alkyl, C1-C6 haloalkyl; R2 is selected from hydrogen, C1-C6 alkyl, C1-C6 haloalkyl; R3 is selected from hydrogen, cinnamoyl, pyrazoloyl, and the hydrogen on the pyrazoloyl may be substituted by one or more of the following substituents, and the substituents are selected from C1-C6 alkyl and C1-C6 haloalkyl.

2. The compound according to claim 1, characterized in that In the general formula I: X1 is selected from methyl; X2 is selected from methylsulfonyl; n is selected from 2; R1 is selected from C1-C3 alkyl; R2 is selected from hydrogen, methyl; R3 is selected from hydrogen, cinnamoyl, pyrazoloyl, and the hydrogen on the pyrazoloyl may be substituted by one or more of the following substituents, and the substituents are selected from C1-C3 alkyl or C1-C3 haloalkyl.

3. Use of the compound of general formula I according to claim 1 for controlling weeds.

4. A herbicidal composition, characterized in that: The herbicidal composition comprises an active substance and an agriculturally acceptable carrier, wherein the active component is the compound of the general formula I described in claim 1, and the weight percentage of the active component in the composition is 1-99%.

5. A method for controlling weeds using the herbicidal composition according to claim 4, characterized in that: Applying a herbicidally effective amount of the herbicidal composition according to claim 4 to weeds or a growth medium or site of weeds.

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