JPS6250444B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is based on the general formula [In the formula, X represents a halogen atom, and Y represents an oxygen atom or a sulfur atom. ] The present invention relates to a herbicide (hereinafter referred to as the composition of the present invention) characterized by containing the 1,4-benzothiazine derivative shown below as an active ingredient. The compound represented by the general formula () is manufactured by the manufacturing method A, B, C or D shown below. That is, (1) General formula () [In the formula, X represents a halogen atom. ] An aminothiophenol derivative represented by the general formula () UCH ₂ COOH () [wherein U represents a halogen atom. ] By reacting the halogenated acetic acid represented by the formula in the presence of a base, the general formula [In the formula, X is as described above.] ] A 1,4-benzothiazine derivative represented by the following can be produced (hereinafter referred to as production method A). (2) Aminothiophenol derivative represented by general formula () and general formula () [In the formula, V and W each represent a halogen atom. ] By reacting with a halogenated acetyl halide represented by the general formula [In the formula, X is as described above.] ] A 1,4-benzothiazine derivative represented by the following can be produced (hereinafter referred to as production method B). (3) General formula () [In the formula, X is as described above, and Z represents a halogen atom. ] By ring-closing the aminothiophenol derivative represented by, preferably in the presence of a base, the general formula [In the formula, X is as described above.] ] A 1,4-benzothiazine derivative represented by the following can be produced (hereinafter referred to as production method C). (4) General formula () [In the formula, X is as described above. ] By reacting the benzothiazine derivative represented by the formula with phosphorus pentasulfide, the general formula [In the formula, X is as described above. ] A 1,4-benzothiazine derivative represented by the following can be produced (hereinafter referred to as production method D). The composition of the present invention has a herbicidal effect, and is effective against field weeds of the Poaceae family, such as barnyard grass, blackberry, foxtail grass, and staghorn grass, as well as broad-leaved field weeds, such as cyperus, cyperus, purslane, purslane, and chickweed. It also has a strong effect on annual weeds in paddy fields such as snail. The composition of the present invention exhibits strong activity against perennial weeds that have become a problem in recent years, such as Japanese cypress, Japanese cypress, Japanese cypress, Japanese cypress, Japanese cypress, etc., as well as annual weeds, when treated before germination and during the growing season.
Its feature is that it has a wide herbicidal spectrum. In addition, when used in fields, it is highly effective against major weeds in fields, and is effective both in soil treatment before weeds emerge and in foliage treatment in the early stages of growth.
It has excellent properties such as being harmless to major crops such as peanuts and sunflowers, and can be safely used on vegetables such as lettuce and radish. The composition of the present invention is useful not only as a herbicide for paddy rice but also for various grains, vegetables, orchards, lawns, pastures, tea gardens, mulberry gardens, rubber gardens, forests, non-agricultural lands, and the like. Next, the method for producing the composition of the present invention will be explained in more detail. In production method A, the aminothiophenol derivative represented by the general formula () is dissolved in a suitable solvent such as water, ethanol, methanol, benzene, toluene, xylene, tetrahydrofuran, dioxane, ethyl ether, chloroform, carbon tetrachloride, ethyl acetate. , DMF, DMSO, etc., or a mixed solvent thereof, with a suitable base agent, such as a tertiary amine such as pyridine, triethylamine, trimethylamine, or sodium hydroxide, potassium hydroxide, zinc hydroxide, magnesium hydroxide, sodium, sodium hydride. , potassium tertiary butoxide, sodium ethoxide, sodium methoxide, n-butyl lithium, etc., are mixed with a halogenated acetic acid represented by the general formula (), and the mixture is heated to a temperature of 0.5 to 150°C at an appropriate temperature, for example, 0°C to 150°C. Stir for 24 hours, and when using water as a solvent, obtain the desired compound as crystals. When other organic solvents are used, the solvent is distilled off and the residue is washed with water to obtain the desired compound as crystals. In addition, after the aminothiophenol derivative represented by the general formula () is converted into a salt of an alkali metal such as sodium or potassium, an alkaline earth metal such as calcium or barium, or a metal salt such as magnesium or zinc, the aminothiophenol derivative may be prepared without the presence of a base agent. It is also possible to carry out the above reaction to obtain the target compound. These target compounds can be further purified by general purification methods such as recrystallization and column chromatography. In production method B, the aminothiophenol derivative represented by the general formula () is mixed with a suitable solvent such as water, ethanol, methanol, benzene, toluene, xylene, tetrahydrofuran, dioxane, ethyl ether, chloroform, carbon tetrachloride, ethyl acetate. , DMF, DMSO, etc., or a mixed solvent thereof, with a suitable base agent, such as tertiary amines such as pyridine, triethylamine, trimethylamine, or sodium hydroxide, potassium hydroxide, sodium, sodium hydride, potassium tertiary butoxide, sodium ethoxy. Do,
In the presence of sodium methoxide, n-butyllithium, etc., a halogenated acetyl halide represented by the general formula () is mixed and heated at an appropriate temperature, e.g.
After stirring at ℃~150℃ for 0.5~20 hours, pour into water and if crystals precipitate, filter, wash with water, and dry to obtain the desired product. If it does not crystallize, extract with a suitable extraction solvent, dry the solvent, and then evaporate to obtain the desired compound as crystals. These target compounds can be further purified by general purification methods such as recrystallization and column chromatography. In production method C, the aminothiophenol derivative represented by the general formula () is mixed with a suitable solvent such as water, ethanol, methanol, benzene, toluene, xylene, tetrahydrofuran, dioxane, ethyl ether, chloroform, carbon tetrachloride, ethyl acetate. , DMF, DMSO, etc. or a mixed solvent thereof, preferably a suitable base agent such as pyridine, a tertiary amine such as triethylamine, trimethylamine, or sodium hydroxide, potassium hydroxide, sodium, sodium hydride,
In the presence of potassium tertiary butoxide, sodium ethoxide, sodium methoxide, n-butyllithium, etc., at an appropriate temperature, e.g., 0°C to
After stirring at 150°C for 0.5 to 24 hours, the desired compound is obtained as crystals when the solvent is water. When other organic solvents are used, the solvent is distilled off and the residue is washed with water to obtain the desired compound as crystals. These target compounds can be further purified by general purification methods such as recrystallization and column chromatography. In production method D, a benzothiazine derivative represented by the general formula () is mixed with phosphorus pentasulfide in an appropriate solvent such as benzene, toluene, xylene, chloroform, carbon tetrachloride, pyridine, etc. or a mixed solvent thereof at an appropriate temperature, For example 60~
After heating at 140° C. for an appropriate time, for example 1 to 10 hours, the mixture is filtered through Celite while hot, and the solvent is distilled off, or when the solvent is pyridine, poured into water to obtain the desired compound. These target compounds are recrystallized,
It is possible to further purify using general purification means such as column chromatography. Representative examples of compounds represented by the general formula () obtained by the above method are shown in Table 1, but the present invention is of course not limited to these.

【table】

[Table] When actually using the composition of the present invention, the raw material itself may be sprayed, or any formulation form such as granules, wettable powders, emulsions, etc. may be used. In preparing these pharmaceutical products, solid carriers include, for example, mineral powders (kaolin, bentonite, clay, montmorillonite, talc, diatomaceous earth, mica, vermiculite, gypsum, calcium carbonate, apatite, etc.). , vegetable powder (soybean flour,
Wheat flour, wood flour, tobacco flour, starch, crystalline cellulose, etc.), polymer compounds (petroleum resin, polyvinyl chloride, dammar gum, ketone resin, etc.), alumina, waxes, etc. Examples of liquid carriers include alcohols (methyl alcohol, etc.), aromatic hydrocarbons (toluene, benzene, xylene, methylnaphthalene, etc.), chlorinated hydrocarbons (chloroform, carbon tetrachloride, monochlorobenzene, etc.), and ether. (dioxane, tetrahydrofuran, etc.), ketones (acetone, methyl ethyl ketone, cyclohexanone, etc.), esters (ethyl acetate, butyl acetate, ethylene glycol acetate, etc.),
Examples include acid amides (such as dimethylformamide), nitriles (such as acetonitrile), ether alcohols (such as ethylene glycol ethyl ether), and water. The surfactant used for the purpose of emulsification, dispersion, diffusion, etc. may be nonionic, anionic, cationic, or amphoteric. Examples of surfactants used include polyoxyethylene alkyl ether, polyoxyethylene alkylaryl ether, polyoxyethylene fatty acid ester, sorbitan fatty acid ester, polyoxyethylene sorbitan fatty acid ester, oxyethylene oxypropylene polymer, polyoxy Ethylene alkyl phosphate, fatty acid salt, alkyl sulfate, alkyl sulfonate,
These include alkylaryl sulfonates, alkyl phosphate ester salts, polyoxyethylene alkyl sulfate esters, quaternary ammonium salts, oxylalkyl amines, and the like, but are of course not limited to these. Furthermore, for these purposes, gelatin, casein, sodium alginate, starch, agar, polyvinyl alcohol, and the like may be used as adjuvants, if necessary. Examples of formulations are shown below. Formulation Example 1 25 parts by weight of compound (1), 2.5 parts by weight of dodecylbenzenesulfonate, 2.5 parts by weight of lignosulfonate and 70 parts by weight of diatomaceous earth are thoroughly ground and mixed to obtain a wettable powder. Formulation example 2 Compound (2) 30 parts by weight, emulsifier Solpol SM100
(Toho Chemical registered trademark name) 10 parts by weight and xylene
Mix 60 parts by weight thoroughly to obtain an emulsion. Formulation Example 3 5 parts by weight of compound (1), 1 part by weight of white carbon, 5 parts by weight of lignin sulfonate and clay
After thoroughly grinding and mixing 89 parts by weight, adding water and kneading well, the mixture is granulated and dried to obtain granules. Formulation Example 4 3 parts by weight of compound (4), 1 part by weight of isopropyl phosphate, 66 parts by weight of clay and 30 parts by weight of talc are thoroughly ground and mixed to obtain a powder. Formulation Example 5 40 parts by weight of bentonite, 5 parts by weight of lignin sulfonate and 55 parts by weight of clay are pulverized and mixed, water is added and kneaded, followed by granulation and drying to produce granules containing no active ingredient. Add 5 parts of compound (5) to 95 parts by weight of this granule.
Granules are obtained by impregnating parts by weight. Formulation Example 6 Granules are obtained by impregnating 95 parts by weight of bentonite sieved to 16-48 mesh with 5 parts by weight of compound (1). Furthermore, the composition of the present invention can be used in combination with other herbicides in order to improve its effectiveness as a herbicide, and in some cases a synergistic effect can be expected.
Examples include phenoxy herbicides such as 2,4-dichlorophenoxyacetic acid; 2-methyl-4-chlorophenoxyacetic acid (including esters and salts), and 2,4-dichlorophenyl-4'-nitrophenyl. Ether; 2,4,6-trichlorophenyl-4'-nitrophenyl ether; 2-chloro-4-trifluoromethylphenyl-3'-ethoxy-4'-nitrophenyl ale; 2,4-dichlorophenyl -4'-nitro-3'-methoxyphenyl ether; diphenyl ether herbicides such as 2,4-dichlorophenyl-3'-methoxycarbonyl-4'-nitrophenyl ether, 2-chloro-
4,6-bisethylamino-1,3,5-triazine; 2-chloro-4-ethylamino-6-isopropylamino-1,3,5-triazine; 2-
Methylthio 4,6-bisethylamino 1,
3,5-triazine; 2-methylthio 4,6-
Triazine herbicides such as bisisopropylamino-1,3,5-triazine, 3-(3,4-dichlorophenyl)-1,1-dimethylurea; 3-
(3,4-dichlorophenyl)-methoxy-1-
Urea herbicides such as methylurea, 1-(2,2-dimethylbenzyl)-3-P-tolylurea,
Carbamate herbicides such as isopropyl-N-(3-chlorophenylcarbamate; methyl-N-(3,4-dichlorophenyl)carbamate, S
-(4-Chlorbenzyl)-N,N-diethylthiol carbamate; Thiol carbamate herbicides such as S-ethyl-N,N-hexamethylenethiol carbamate, 3,4-dichloropropionanilide; N-methoxymethyl- 2,6-diethyl-α-chloroacetanilide; 2-chloro-
2',6'-diethyl-N-(butoxymethyl)-acetanilide; N-chloroacetyl-N-(2,
Acid anilide herbicides such as 6-diethylphenyl)-glycine ethyl ester; uracil herbicides such as 5-bromo-3-secondary-butyl-6-methyluracil; 3-cyclohexyl-5,6-trimethyleneuracil; , 1,1'-dimethyl-4,4
- Pyridinium chlorine herbicides such as bispyridinium chloride, N,N-bis(phosphonomethyl)
-Glycine, O-ethyl-O-(2-nitro-5
-methylphenyl)-N-secondary butyl phosphoroamidothioate, S-(2-methyl-1
-Piperidylcarbonylmethyl)-O,O-di-
Phosphorous herbicides such as n-propyldithiophosphate, toluidine herbicides such as α,α,α-trifluoro-2,6-dinitro-N,N-dipropyl-P-toluidine, 5-tertiarybutyl-3
-(2,4-dichloro-5-isopropoxyphenyl)-1,3,4-oxadiazolin-2-one; 3-isopropyl-1H-2,1,3-benzothiadiazine-(4) -3H-one-2,2-dioxide, α(β-naphthoxy)-propionanilide, 4-(2,4-dichlorobenzoyl)-
Examples include, but are not limited to, 1,3-dimethylpyrazol-5-yl p-toluenesulfonate. Furthermore, the composition of the present invention can be used in combination with insecticides, nematicides, fungicides, plant growth regulators, fertilizers, etc., if necessary. Next, a production example of a compound represented by the general formula [] will be shown as a reference example. Reference example 1 (Production method A) After dissolving 690 mg of sodium hydroxide in 40 ml of water, 2.5 ml of 2-amino-3-chlorothiophenol
Dissolve g and add 2.4 g of bromoacetic acid while stirring. After stirring at 70°C for 3 hours, the precipitated crystals were filtered, washed with water, and dried to obtain the desired 5-chloro-2,3-dihydro-1,4-benzothiazine.
3-on m.p 160-161°C) 2.98 g was obtained.

[Table] Reference Example 2 (Production method A) 1.6 g of hebromoacetic acid in which 2.0 g of zinc salt of 2-amino-3-chlorothiophenol was suspended in 30 ml of water.
was added and stirred at 70°C for 3 hours. After filtering the precipitated crystals, they are washed with water and dried to obtain the desired 5-chloro-2,3-dihydro-1,4-benzothiazine-
1.8 g of 3-one (m.p 160-161°C) was obtained.

[Table] Reference example 3 (Production method B) 2-amino-3-bromothiophenol 2.0g
and 1.7 g of pyridine are dissolved in 20 ml of benzene,
While stirring, 1.2 g of chloroacetyl chloride was gradually added dropwise at room temperature (25°C). After dropping, heat
After stirring at 80°C for 5 hours, it was filtered while cold, and the solvent was distilled off. The resulting residue was recrystallized from chloroform to obtain the desired 5-bromo-2,3-dihydro-
1,4-Benzothiazin-3-one (mp.146~
147°C) 2.0g was obtained.

[Table] Reference Example 4 (Production method C) 2-chloroacetylamino-3-fluorothiophenol in 2N aqueous sodium hydroxide solution
After adding 2.0 g and stirring at room temperature (25°C) for 3 hours, the precipitated crystals were filtered, washed with water, and dried to obtain the desired 5-fluoro-2,3-dihydro-1,
4-Benzothiazin-3-one (mp.190-191
℃) 1.5g was obtained.

[Table] Reference Example 5 (Production method D) Add 2.0 g of 5-chloro-2,3-dihydro-1,4-benzothiazin-3-one and 2.0 g of phosphorus pentasulfide to 5 ml of pyridine and heat at 120°C for 20 minutes. After stirring, pour into 50ml of diluted hydrochloric acid, filter the precipitated crystals, wash with water, dry and recrystallize from ethanol to obtain the desired 5-chloro-2,3-dihydro-1,4.
-Benzothiazine-3-thione (mp.138-140
℃) 1.9g was obtained.

[Table] Next, the present invention will be explained in more detail with reference to Examples. In addition, the compound name is shown by the number of the said example. Example 1 Soil treatment test after sowing in upland field Weed seeds of crabgrass, blueberry, and pigweed and crop seeds of soybean and sunflower were sown in 3-dimensional bisque pots, and after covering with soil, a predetermined amount of the raw material was made into an emulsion, diluted with water, The soil was treated with a hand sprayer. Thereafter, the plants were grown in a greenhouse, and 20 days after treatment, the herbicidal efficacy and crop damage were observed. The results are shown in Table 2. Evaluation of herbicidal efficacy was expressed as a number from 0 to 5 as shown below. However, phytotoxicity of crops is also shown using the same criteria as herbicidal efficacy. 0... Weed suppression rate 0-9% 1... 10-29% 2... 30-49% 3... 50-69% 4... 70-89% 5... 90-100%

[Table] Example 2 A Wagner pot with a diameter of 14 cm filled with 1.5 kg of paddy soil was turned into a paddy field, and rice seedlings at the 3-leaf stage were transplanted.
Furthermore, Japanese mulberry seeds were sown, and tubers of Japanese cypress and Cyperus japonica were planted, and a predetermined amount of the chemical was applied to the flooded soil. 25 days after drug treatment, the transplanted or sown plants and naturally occurring coryza;
We investigated the herbicidal efficacy and degree of chemical damage for broad-leaved weeds such as azalea and azalea. The results are shown in Table 3. Regarding the treatment method, a predetermined amount of the drug was treated in the form of a wettable powder at a rate of 15 c.c. per pot. During the treatment, the solution was added dropwise using a pipette. Evaluation of herbicidal efficacy was expressed as a number from 0 to 5 as shown below. 0... Weed suppression rate 0-9% 1... 10-29% 2... 30-49% 3... 50-69% 4... 70-89% 5... 90-100% Plant damage Regarding plant height, number of tillers, and total amount (air-dry weight), the ratio of plant height to the untreated plot was calculated, and the worst value among the three factors was taken and evaluated on a scale of 0 to 5. 0... Ratio to untreated area 100% 1... 〃 90-99% 2... 〃 80-89% 3... 〃 60-79% 4... 〃 40-59% 5... 〃 0-39%

【table】

[Table] Example 3 A plastic tray measuring 35 cm in length, 25 cm in width, and 10 cm in height was filled with field soil, and seeds of blueberry, pigweed, red-winged grass, and barnyard grass were sown, and after growing in a greenhouse for 14 days, a prescribed amount of chemicals were applied to the plants. The leaves were treated with a small sprayer from above the body. The growth status of each plant at the time of treatment was 2 to 6 cm in plant height for the Japanese amberjack and pigweed, and 4 to 10 cm in plant height for the Japanese barley and Japanese barnyard grass. After the chemical treatment, the plants were kept in a greenhouse for another 20 days, and the herbicidal efficacy of each plant was investigated. The results are shown in Table 4. At the time of the survey, the above-ground parts of the plants that remained withered were harvested to measure the production volume, and the weight of the untreated area was 100%.
The herbicidal efficacy was evaluated according to the following criteria by calculating the remaining weed percentage. The processing agent was prepared by dispersing a predetermined amount of the agent in a wettable powder in 3 parts of water per are, and adding a spreading agent.

【table】

【table】

Claims (1)

[Claims] 1. General formula [In the formula, X represents a halogen atom, and Y represents an oxygen atom or a sulfur atom. ] A herbicide characterized by containing a 1,4-benzothiazine derivative represented by the following as an active ingredient.