JPS6334870B2 - - 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, X and Y are a halogen atom, a nitro group, or a trifluoromethyl group, and Z is a halogen atom) and a herbicide containing them. . In the definition of the above general formula, examples of the halogen atom include fluorine, chlorine, bromine, and iodine. The pyrazole derivative of the present invention can be produced, for example, by the method described below. In the above reaction formula, X, Y and Z are as described above. Further, 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. Next, specific synthesis examples according to the present invention will be described. Synthesis example 1,3-dimethyl-4- in a 4-necked flask
Add 1.0g of (2,4-dichlorobenzoyl)-5-hydroxypyrazole and methyl ethyl ketone.
It was dissolved in 20ml. Add to this anhydrous potassium carbonate 0.54
Add 1,1-dimethyl-2 while stirring.
-Chloroethyl bromomethyl ketone (0.75 g) was added dropwise, 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. After separating this with a silica gel column (eluent: methylene chloride), methylene chloride was distilled off,
1,3-dimethyl-4-(2,4
0.7 g of -dichlorobenzoyl)-5-(1,1-dimethyl-2-chloropropionylmethoxy)pyrazole was obtained. Specific compounds of the present invention obtained in the same manner as in the above synthesis examples are described below. Compound No. 1 1,3-dimethyl-4-(2,4-
dichlorobenzoyl)-5-(1,
1-dimethyl-2-chloropropionylmethoxy)pyrazole
mp58～60℃ Compound No.2 1,3-dimethyl-4-(2-chloro-4-trifluoromethylbenzoyl)-5-(1,1-dimethyl-
2-chloropropionylmethoxy)
Pyrazole mp76-77.5℃ Compound No. 3 1,3-dimethyl-4-(2-nitro-4-chlorobenzoyl)-5-
(1,1-dimethyl-2-chloropropionylmethoxy)pyrazole
n ²⁶ _D 1.5925 Compound No. 4 1,3-dimethyl-4-(2,4-
dichlorobenzoyl)-5-(1,
1-Dimethyl-2-bromopropionylmethoxy)pyrazole White crystals As shown in the test examples below, the pyrazole derivative of the present invention exhibits suitable effects when used as an active ingredient of herbicides. 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 fields, fields, orchards, mulberry orchards, mountain forests, farm roads, grounds, and factory grounds, and the application method is also 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. For example, the blending ratio at the time of formulation is 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.
It is suitable that the surfactant content is 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, soil, 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 to these descriptions. Test Example 1 Paddy soil was poured into a 1/5000-acre pot and the pot was saturated with water, followed by sowing of food millet seeds and lightly covering the pot with soil.
After germination in the field, the plants were grown under water at a depth of about 3 cm, and when coleoptiles appeared, a predetermined amount of an aqueous dispersion of the compound of the present invention was added dropwise. 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. Degree of growth suppression 5: Complete dead state 〓 〓 1: Growth similar to untreated area

[Table] Test Example 2 A 1/5000-sized earth 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 reached the one-leaf stage, the water depth was set to about 3 cm, and a predetermined amount of an aqueous dispersion of the compound of the present invention was dropped into the water. The growth state was observed 3 weeks after the chemical solution treatment, and the degree of growth inhibition was evaluated using the same criteria as in Test Example 1, and the results shown in Table 2 were obtained.

【table】

[Table] Test Example 3 After filling a 1/5000-sized pot with paddy soil and saturating it with water, tubers of Cyperus japonica were planted. After germination in the field, the plants were grown in water at a depth of about 3 cm, and when they reached about 0.5 leaf stage, a predetermined amount of an aqueous dispersion of the compound of the present invention was added dropwise. The growth state was observed 3 weeks after the chemical solution treatment, and the degree of growth inhibition was evaluated using the same criteria as in Test Example 1, and the results shown in Table 3 were obtained.

【table】

[Table] Formulation example 1 (1) Bentonite 58 parts by weight (2) Siegrite 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,
Granules were obtained by spraying 7 parts by weight of 4-dichlorobenzoyl)-5-(1,1-dimethyl-2-chloropropionylmethoxy)pyrazole. Formulation example 2 (1) Siegrite 78 parts by weight (2) Lavelin S (product name: Daiichi Kogyo Seiyaku)
2 parts by weight (3) Solpol 5039 (Product name: Toho Chemical Industries)
5 parts by weight (4) Carplex (product name: manufactured by Shionogi & Co., Ltd.)
15 parts by weight mixture of each of the above components and 1,3-dimethyl-4
-(2-chloro-4-trifluoroethylbenzoyl)-5-(1,1-dimethyl-2-chloropropionylmethoxy)pyrazole in a weight ratio of 4:1 to obtain a wettable powder.

Claims (1)

[Claims] 1. General formula A pyrazole derivative represented by the formula (wherein X and Y are a halogen atom, a nitro group or a trifluoromethyl group, and Z is a halogen atom). 2 General formula A herbicide characterized by containing a pyrazole derivative represented by the formula (wherein X and Y are a halogen atom, a nitro group, or a trifluoromethyl group, and Z is a halogen atom) as an active ingredient.