JPS6334867B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to 1,3-dimethyl-4-(2,4-dichlorobenzoyl)-5-pivaloylmethoxypyrazole, and to a herbicide containing this compound as an active ingredient. The compound of the present invention can be produced, for example, by the method described below. In the above reaction formula, 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, Hal is a halogen atom. 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, and as catalysts, aluminum chloride, zinc chloride, and dichloride can be used. Metal chlorides such as diiron can be used. Synthesis example 1,3-dimethyl-4- in a 4-necked flask
Add 0.45g of (2,4-dichlorobenzoyl)-5-hydroxypyrazole and methyl ethyl ketone.
It was dissolved in 15ml. Add to this 0.5 anhydrous potassium carbonate
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. After separating this with a silica gel column (eluent: methylene chloride), the methylene chloride was distilled off, and 1,3-dimethyl-4-(2,4-dichlorobenzoyl)-5
-0.5g of pivaloylmethoxypyrazole was obtained. As shown in the test examples described later, the pyrazole derivative of the present invention exhibits suitable effects when used as an active ingredient of a herbicide. 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 has the above-mentioned active ingredients, namely 1,
In addition to directly dissolving or dispersing 3-dimethyl-4-(2,4-dichlorobenzoyl)-5-pivaloylmethoxypyrazole in water to make an aqueous solution or dispersion, diatomaceous earth, slaked lime, calcium carbonate,
Carriers such as talc, white carbon, kaolin, bentonite, and ziecrite; benzene, toluene, xylene, solvent naphtha, ethanol,
Solvents such as dioxane, acetone, isophorone, methyl isobutyl ketone, dimethylformamide, dimethyl sulfoxide, water; and, if necessary, sodium alkyl sulfate, sodium alkylbenzenesulfonate, sodium lignin sulfonate, polyoxyethylene lauryl ether, polyoxyethylene alkyl Anionic or nonionic surfactants such as aryl ether, polyoxyethylene fatty acid ester, polyoxyethylene sorbitan fatty acid ester, etc. are blended as appropriate and formulated into emulsions, wettable powders, solutions, powders, and granules. It can be used as For example, the blending ratio at the time of formulation is 1 to 90% of the active ingredient.
Suitable weight percentage is preferably 1 to 70% by weight, carrier or solvent 5 to 99% by weight, preferably 25 to 99% by weight, and surfactant 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 categorically determined due to differences in weather conditions, land transfer conditions, drug formulation, application timing, application method, type of target weed, etc., but it is generally expressed as the amount of active ingredient applied per are. The amount is 1 to 500 g, preferably 10 to 100 g. 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 After filling a 1/5000-sized pot with paddy soil and making it saturated with water, food millet seeds were sown and lightly covered with soil.
After germination in the field, the seeds were grown under water at a depth of about 3 cm, and when coleoptiles appeared, a predetermined amount of the compound of the present invention was added dropwise. Three weeks after the chemical treatment, the growth status of the barnyard grass was observed, and the degree of growth inhibition was determined using a 5-point scale from 1 to 5 (1 indicates that the growth was similar to that of the untreated area and no growth inhibition was observed, and 5 indicates that the growth was completely suppressed). When evaluated, the amount of applied active ingredient was 30g/a, 15g/a, 15/2g/a and 15/4
The g/a test group was 5 in all cases. Test Example 2 A 1/5000-sized pot was filled with soil and flooded with water, and seeds of firefly were sown, as well as tubers of Urikawa were planted and grown in a greenhouse. When the firefly and urikawa reach the one-leaf stage, the water depth is set to about 3 cm.
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 the following table were obtained.

[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. Granules were obtained by spraying 7 parts by weight of the compound of the present invention. Formulation example 2 (1) Siegrite 78 parts by weight (2) Lavelin S (product name: Daiichi Kogyo Seiyaku)
2 parts by weight (3) Solbol 5039 (product name: manufactured by Toho Chemical Industries)
5 parts by weight (4) Carplex (product name: manufactured by Shionogi & Co., Ltd.)
15 parts by weight of the mixture of each of the above components and the compound of the present invention:
A wettable powder was obtained by mixing at a weight ratio of 1:1.

Claims (1)

[Claims] 1 1,3-dimethyl-4-(2,4-dichlorobenzoyl)-5-pivaloylmethoxypyrazole. 2 A herbicide containing 1,3-dimethyl-4-(2,4-dichlorobenzoyl)-5-pivaloylmethoxypyrazole as an active ingredient.