JPS6155505B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to pyrazole derivatives and herbicides containing them as active ingredients. More specifically, the present invention relates to the general formula (In the formula, one of X ¹ and X ² is a trifluoromethyl group, the other is a hydrogen atom, a halogen atom, or a trifluoromethyl group, and Y is a lower alkyl group,
or a phenyl group optionally substituted with halogen or lower alkyl), and herbicides containing them. In the definition of the general formula (), the halogen atoms include fluorine, chlorine, bromine, and iodine, and the lower alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, and tert-butyl.
Examples include butyl. The pyrazole derivative of the present invention can be produced, for example, by the method described below. In the above reaction formula, X ¹ , X ² and Y are as described above, and Hal is a halogen atom. Examples of the solvent used in the above reaction include acetone, ketones such as methyl ethyl ketone, and dimethylformamide, and examples of the alkaline substance include potassium carbonate, sodium carbonate, and sodium hydroxide. Furthermore, when a cuprous halide catalyst such as copper iodide or copper fluoride is present, the reactivity can be improved. In the above reaction formula, X ¹ , X ² , Y and Hal are as described above. In the reaction between compound () and compound (), the same solvent, alkaline substance, and catalyst as in the case of the above-mentioned production method (A) can be used. In the reaction between compound () and compound (), solvents such as ethers such as diethyl ether and tetrahydrofuran, and halogenated hydrocarbons such as tetrachloroethane can be used.Aluminum chloride, zinc chloride, and chloride can be used as catalysts. Metal chlorides such as ferric iron can be used. The pyrazole derivative thus obtained is
Furthermore, it can be converted into other pyrazole derivatives of the present invention by conventional methods. Next, specific synthesis examples according to the present invention will be described. Synthesis Example 1 1,3-dimethyl-4-(2-chloro-4-trifluoromethylbenzoyl)-5-benzoylmethoxypyrazole 1,3-dimethyl-4-(2-chloro-4-trifluoromethylbenzoyl)-5-benzoylmethoxypyrazole
-chloro-4-trifluoromethylbenzoyl)
3.0 g of -5-hydroxypyrazole was added and dissolved in 30 ml of methyl ethyl ketone. To this was added 2.6 g of anhydrous potassium carbonate, 1.84 g of phenacyl bromide was added while stirring, and the mixture was reacted under reflux for 2 hours. After the reaction was completed, the product was left to cool, filtered, and methyl ethyl ketone was distilled off to obtain a crude product. Apply this to a silica gel column (eluent: methylene chloride)
3.8 g of the target product with a melting point of 78-80°C was obtained. Synthesis example 2 1,3-dimethyl-4-(2-chloro-4-trifluoromethylbenzoyl)-5-pivaloylmethoxypyrazole 1,3-dimethyl-4-(2
-chloro-4-trifluoromethylbenzoyl)
0.5 g of -5-hydroxypyrazole was added and dissolved in 15 ml of methyl ethyl ketone. To this was added 0.5 g of anhydrous potassium carbonate, and while stirring, 0.3 g of tert-butyl bromomethyl ketone was added, and the mixture was reacted under reflux for 2 hours. After the reaction was completed, the product was filtered and the solvent was distilled off to obtain a crude product. This was separated using a silica gel column (eluent: methylene chloride) to obtain 0.6 g of the desired product as a brown oil. Specific compounds of the present invention are described below. Compound No. 1 1,3-dimethyl-4-(2-chloro-4-trifluoromethylbenzoyl)-5
-Benzoylmethoxypyrazole mp78〜80
°C Compound No.2 1,3-dimethyl-4-(2-trifluoromethyl-4-chlorobenzoyl)-5
-Benzoylmethoxypyrazole mp59〜61
°C Compound No.3 1,3-dimethyl-4-(2-chloro-4-trifluoromethylbenzoyl)-5
-pivaloylmethoxypyrazole Brown oil compound No. 4 1,3-dimethyl-4-(2-chloro-4-trifluoromethylbenzoyl)-5
-(2-Methylbenzoylmethoxy)pyrazole Brown oil compound No. 5 1,3-dimethyl-4-(4-trifluoromethylbenzoyl)-5-benzoylmethoxypyrazole Yellow-brown oil compound No. 6 1,3- Dimethyl-4-(4-trifluoromethylbenzoyl)-5-pivaloylmethoxypyrazole Compound No. 7 1,3-dimethyl-4-(2-fluoro-4-trifluoromethylbenzoyl)-
5-benzoylmethoxypyrazole compound No. 8 1,3-dimethyl-4-(2-chloro-4-trifluoromethylbenzoyl)-5
-(4-bromobenzoylmethoxy)pyrazole Brown oil The pyrazole derivative of the present invention exhibits suitable effects when used as an active ingredient of a herbicide, as shown in the test examples described later. In particular, it effectively controls harmful weeds such as barnyard grass, cyperus japonica, cyperus japonica, bulrush, scallops, and other plants without causing any substantial harm to crops such as rice. The herbicide of the present invention has an excellent herbicidal effect on various weeds, so its application range is wide-ranging, including rice paddies, fields, orchards, mulberry orchards, mountain forests, farm roads, grounds, and factory grounds. Application methods include soil treatment. , foliage treatment can be selected as appropriate. The herbicide of the present invention can be prepared by directly dissolving or dispersing the above-mentioned active ingredient, i.e., a pyrazole derivative, in water to form an aqueous solution or dispersion.
Carriers such as kaolin, bentonite, and ziecrite; solvents such as benzene, toluene, xylene, solvent naphtha, ethanol, dioxane, acetone, isophorone, methyl isobutyl ketone, dimethyl formamide, dimethyl sulfoxide, and water; and, if necessary, sodium alkyl sulfate. , anionic or nonionic surfactants such as sodium alkylbenzene sulfonate, sodium lignin sulfonate, polyoxyethylene lauryl ether, polyoxyethylene alkylaryl ether, polyoxyethylene fatty acid ester, polyoxyethylene sorbitan fatty acid ester, etc. They can be appropriately blended and used in the form of emulsions, wettable powders, solutions, powders, and granules. The blending ratio in formulation is, for example, 1 to 90% by weight of the active ingredient, preferably 1 to 70% by weight, and 5 to 99% by weight of the carrier or solvent, preferably 25% by weight.
99% by weight of the surfactant, preferably 0 to 30% by weight, preferably 1 to 20% by weight. Furthermore, the herbicide of the present invention can be mixed or used in combination with other herbicides, pesticides such as insecticides, fungicides, fertilizers, soils, etc., and in this case may exhibit even better effects. The appropriate amount of the herbicide of the present invention to be applied cannot be determined unconditionally due to differences in weather conditions, soil conditions, drug formulation, application timing, application method, type of target weed, etc., but in general, the amount of active ingredient applied per are is 1. ~500g, preferably 10-100g. Next, examples of plant tests and formulations of herbicides according to the present invention will be described, but of course the present invention is not limited only to these descriptions. Test Example 1 After filling a 1/5000-sized pot with paddy soil and filling it with water, millet seeds for food were sown, and the pot was lightly covered with soil.
After germination in the field, the seeds were grown under water at a depth of approximately 3 cm, and when coleoptiles appeared, an aqueous dispersion of each test compound was added dropwise to give a concentration of 100 g/a per active ingredient. Three weeks after the chemical solution treatment, the growth state was observed with the naked eye, and the degree of growth inhibition was expressed based on the following criteria (5-point scale from 1 to 5), and the results are listed in Table 1. Growth suppression degree 5: Complete dead state 〓 〓 1: Growth similar to untreated area

[Table] Experimental Example 2 A test was conducted in the same manner as in Test Example 1 except that the amount of active ingredient in the drug solution was changed, and the results shown in Table 2 were obtained.

[Table] Test Example 3 A 1/5000-sized earthen pot was filled with soil and flooded with water, and seeds of firefly were sown, and tubers of seaweed were planted and grown in a greenhouse. When the firefly and urikawa reach the two-leaf stage, the water depth is set to about 3 cm.
An aqueous dispersion of each test compound was added dropwise. After 3 weeks of chemical treatment, the growth condition was visually observed, and Test Example 1
The degree of growth inhibition was expressed using the same criteria as in the case of , and the results shown in Table 3 were obtained.

[Table] Formulation example 1 (1) Bentonite 58 parts by weight (2) Dikrite 30 parts by weight (3) Sodium ligninsulfonate 5 parts by weight The above ingredients were mixed and granulated, and diluted with an appropriate amount of acetone. 1,3-dimethyl-4-(2-
Chloro-4-trifluoromethylbenzoyl)-
A herbicide (granulated) of the present invention was obtained by spraying 7 parts by weight of 5-pivaloylmethoxypyrazole. Formulation example 2 (1) 20 parts by weight of 1,3-dimethyl-4-(2-trifluoromethyl-4-chlorobenzoyl)-5-benzoylmethoxypyrazole (2) 75 parts by weight of dicrite (3) Lavelin S ( Product name: Daiichi Kogyo Seiyaku)
2 parts by weight (4) Sodium ligninsulfonate 3 parts by weight The above components were uniformly mixed to obtain a herbicide (wettable powder) of the present invention. Formulation example 3 (1) Zikrite 78 parts by weight (2) Labelin (product name: manufactured by Daiichi Kogyo Seiyaku) 2 parts by weight (3) Solpol 5039 (product name: manufactured by Toho Chemical Industries)
5 parts by weight (4) Carplex (product name: Shionogi & Co., Ltd.)
15 parts by weight The mixture of the above components (1) to (4) and 1,3-dimethyl-4-(2-chloro-4-trifluoromethylbenzoyl)-5-benzoylmethoxypyrazole in a 4:1 weight ratio The herbicide (wettable powder) of the present invention was obtained by mixing.

[Brief explanation of the drawing]

Figures 1 to 3 show the compounds of the present invention, 1,3-dimethyl-4-(2-chloro-4-trifluoromethylbenzoyl)-5-pivaloylmethoxypyrazole, 1,3-dimethyl-4-(2 -Chloro-4
-trifluoromethylbenzoyl)-5-(2-methylbenzoylmethoxy)pyrazole, 1,3-
It is an infrared absorption spectrum of dimethyl-4-(4-trifluoromethylbenzoyl)-5-benzoylmethoxypyrazole.

Claims (1)

[Claims] 1. General formula (In the formula, one of X ¹ and X ² is a trifluoromethyl group, the other is a hydrogen atom, a halogen atom, or a trifluoromethyl group, and Y is a lower alkyl group,
or a phenyl group optionally substituted with halogen or lower alkyl). 2 General formula (In the formula, one of X ¹ and X ² is a trifluoromethyl group, the other is a hydrogen atom, a halogen atom, or a trifluoromethyl group, and Y is a lower alkyl group,
or phenyl group optionally substituted with halogen or lower alkyl) as an active ingredient. 3 General formula (In the formula, one of X ¹ and X ² is a trifluoromethyl group, and the other is a hydrogen atom, a halogen atom, or a trifluoromethyl group) and a compound represented by the general formula (In the formula, Hal is a halogen atom, and Y is a lower alkyl group or a phenyl group optionally substituted with halogen or lower alkyl) in the presence of an alkaline substance, and the general formula A method for producing a pyrazole derivative represented by the formula (wherein X ¹ , X ² and Y are as described above).