JPH038348B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to specific benzyloxybenzoic acid amide derivatives and herbicides containing the same. The present inventors focused on benzyloxybenzoic acid compounds and investigated their herbicidal activity, and found that
The inventors discovered the unique action of a specific benzyloxybenzoic acid amide derivative and completed the present invention. The first invention of the present invention is the general formula [] [However, in the formula, X is a hydrogen atom, a halogen atom,
Represents a lower alkyl group, lower alkoxy group, trifluoromethyl group or nitro group. n is 1 to 3
and when n is 2 or 3, X may be the same or different from each other. ] is a metabenzyloxybenzoic acid amide derivative represented by
The second invention is a herbicide containing the compound. Next, typical metabenzyloxybenzoic acid amide derivatives according to the present invention are shown.

【table】

[Table] The compounds of the present invention can be synthesized by various methods shown below. (i) General formula [However, in the formula, X and n are as defined above. Y represents a halogen atom. ] A benzyl halide represented by the following is reacted with 1-(3-hydroxybenzoyl)pyrrolidine. That is, benzyl halides [] and 1-
(3-Hydroxybenzoyl)pyrrolidine is reacted by heating in the absence of a solvent or in an inert organic solvent in the presence of a dehydrohalogenating agent. Suitable inert solvents are toluene, xylene, dimethylformamide, dimethylsulfoxide, diglyme, etc., or mixtures thereof. As the dehydrohalogenating agent, sodium carbonate, potassium carbonate, etc. are preferably used. The reaction temperature and reaction time vary mainly depending on the type of reagent used, but are generally 50°C to reflux temperature, 1
A period of 10 to 10 hours is suitable. After the reaction is completed, the target compound can be obtained from the reaction mixture according to a conventional method. (ii) General formula [However, in the formula, X and n are as defined above. ] Metabenzyloxybenzoic acid or its reactive derivative represented by the following is reacted with pyrrolidine. The reactive derivatives mentioned here include acid halides, acid anhydrides, esters, and the like. This reaction is carried out without a solvent or in an inert organic solvent. Among the free acids and reactive radicals, acid chlorides are commonly used and are carried out in the presence of a dehydrochlorination agent. The acid chloride used is synthesized from the free acid and thionyl chloride or phosgene. Suitable inert organic solvents include toluene, xylene, diethyl ether, tetrahydrofuran, dioxane, dichloromethane, carbon tetrachloride, ethyl acetate, etc., or mixtures thereof. Further, as the dehydrochlorination agent, it is appropriate to use, for example, triethylamine, sodium hydrogen carbonate, sodium carbonate, and the like. Since the reaction is generally exothermic, it is usually carried out under cooling. The reaction time varies mainly depending on the reaction temperature and the compound used, but is about instantaneous to several hours. After the reaction is completed, the target compound can be obtained from the reaction mixture according to a conventional method. Next, a typical synthesis example will be shown. Synthesis Example 1 1-{3-(2,6-dichlorobenzyloxy)benzoyl}pyrrolidine 14.3 g of 2,6-dichlorobenzyl chloride,
1-(3-hydroxybenzoyl)pyrrolidine
16.8 g of potassium carbonate and 15.2 g of potassium carbonate were dissolved in 80 ml of dimethylformamide and stirred at 100°C for 2 hours.
After the reaction is complete, pour the reaction mixture into 500ml of water.
The precipitated crystals were separated and dried to obtain 25.3 g of crude crystals. This was recrystallized from a mixed solvent of benzene/n-hexane to obtain 19.8 g of 1-{3-(2,6-dichlorobenzyloxy)benzoyl}pyrrolidine. Melting point 113-115℃, yield 77.3% (benzyl chloride basis) Elemental analysis value C ₁₈ H ₁₇ Cl ₂ NO ₂ Calculated value: C61.70 H4.86 N4.00 Experimental value: C61.57 H4.73 N3. 79 IR (Nujo1 method, cm ^-1 ) 1610 1583 1435 1250 Synthesis example 2 1-{3-(3-nitrobenzyloxy)benzoyl}pyrrolidine 3-nitrobenzyl chloride 5.1g 1-(3
-Hydroxybenzoyl)pyrrolidine (6.2 g) potassium carbonate (5.4 g) was dissolved in dimethylformamide (15 ml) and stirred at 70°C for 5 hours. After the reaction was completed, the reaction mixture was poured into 200 ml of water and extracted with toluene. After washing the toluene layer with water, it was dehydrated with anhydrous magnesium sulfate, and the solvent was distilled off. The residue was recrystallized from a mixed solvent of toluene and ligroin.
1-(3-hydroxybenzoyl)pyrrolidine 7.2
I got g. Melting point 54-57℃, yield 74.2% (based on benzyl chloride) Elemental analysis value as C ₁₈ H ₁₈ H ₂ O ₄ Calculated value: C66.26 H5.52 N8.59 Experimental value: C65.88 H5.31 N8. 73 IR (CCl ₄ solution method, cm ^-1 ) 1610 1520 1430 1342 Synthesis example 3 1-{3-(2,4-dimethylbenzyloxy)benzoyl}pyrrolidine 3-(2,4-dimethylbenzyloxy)benzoic acid chloride Add 10 ml of pyrrolidine to 5.5 g of tetrahydrofuran solution while stirring while cooling in an ice bath.
was added dropwise, and after the addition was completed, the mixture was stirred at room temperature for 30 minutes. After the reaction was completed, the reaction solution was poured into 200 ml of water, and the precipitated crystals were separated and dried to obtain 6.3 g of crude crystals.
This was recrystallized from a mixed solvent of toluene/n-hexane to obtain 5.1 g of 1-{3-(2,4-dimethylbenzyloxy)benzoyl}pyrrolidine.
Melting point 102-104℃, yield 82.3% (carboxylic acid chloride basis) Elemental analysis value as C ₂₀ H ₂₃ NO ₂ Calculated value: C77.67 H7.44 N4.53 Experimental value: C77.84 H7.45 N4.67 IR (Nujo method, cm ^-1 ) 1610 1450 1292 1255 The herbicide of the present invention contains a compound represented by the general formula [] as an active ingredient mixed with various carriers,
It can be obtained by formulating into the form of wettable powders, emulsions, powders, granules, etc. Among the carriers, a commonly used organic solvent is used as the liquid carrier, and a commonly used fine mineral powder is used as the solid carrier. Further, during preparation of the formulation, a surfactant is added to impart emulsifying properties, dispersibility, spreading properties, and the like. Furthermore, other agricultural chemicals such as fertilizers, herbicides, insecticides, and fungicides can also be used in combination. For use as a herbicide, the active ingredient compound is applied in sufficient amounts to achieve the desired herbicidal action.
The amount of application is within the range of 1 to 2000g/10a of active ingredient, but usually 1 to 1000g/10a.
10a, preferably 100 to 500 g/10a, and is used in the form of a wettable powder, emulsion, powder, granule, etc. containing 0.1 to 50% of the active ingredient. To form an emulsion, the active ingredient is dissolved in an agriculturally acceptable organic solvent and a solvent-soluble emulsifier is added.
Suitable solvents are generally immiscible with water and include
Hydrocarbons, chlorinated hydrocarbons, ketones, esters,
Organic solvents such as alcohols and amides. Useful solvents may include toluene, xylene, naphtha, perchloroethylene, cyclohexanone, isophorone and dimethylformamide or mixtures thereof. Particularly suitable solvents are aromatic hydrocarbons and ketones, but mixtures of solvents are commonly used. The surfactant used as an emulsifier is approximately
It accounts for 0.5 to 20 parts by weight and may be anionic, cationic, or nonionic. Anionic surfactants include alcohol sulfates or sulfonates, alkylaryl sulfonates or sulfosuccinates, such as calcium dodecylbenzenesulfonate or sodium dioctylsulfosuccinate. Cationic surfactants include fatty alkyl amine salts and fatty acid alkyl quaternary salts, such as laurylamine hydrochloride or lauryldimethylbenzylammonium chloride. Nonionic emulsifiers that can be used include alkylphenols, fatty alcohols, mercaptans or ethylene oxide adducts of fatty acids, such as polyethylene glycol esters of stearic acid or polyethylene glycol ethers of palmityl alcohol or octylphenol. The concentration of active ingredient is between 5 and 80 parts by weight, especially
A suitable range is 10 to 30 parts by weight. Wettable powders are prepared by adding the active ingredient to an inert finely divided solid carrier and a surfactant. There are 5 active ingredients
It is common for surfactants to be present in the range of 50 parts by weight and from 0.5 to 20 parts by weight. Solid carriers commonly used for formulating the active ingredients are naturally occurring clays, silicates and silicas, limes and carbonates and organic carriers. Typical examples of these are kaolin, Siegrite, Fuller's earth,
Talc, diatomaceous earth, magnesium lime, dolomite and walnut flour. Commonly used emulsifiers and wetting agents are polyoxyethylenated alkylphenols, fatty alcohols, fatty acids and alkylamines, alkylarylsulfonates and dialkylsulfosuccinates, and the like. Spreading agents include materials such as glycerin mannitus laurate and conjugates of oleic acid and polyglycerin modified with phthalic anhydride.
As the dispersant, a sodium salt of a copolymer of maleic anhydride and olefin, such as diisobutylene, sodium lignin sulfonate, and sodium formaldehyde-naphthalene sulfonate are used. Powders are prepared by combining the active ingredient with inert carriers customary for the manufacture of powders, such as talc, finely divided clay, diatomaceous earth, magnesium carbonate or wheat flour. Concentrated powders are commonly prepared in which the active ingredient is present in the range of 10 to 80 parts by weight, but for application as a herbicide, further solids are added to dilute to about 1 to 20 parts by weight. Granules are made by incorporating the active ingredient into agriculturally acceptable carriers such as bentonite, kaolin clay, diatomaceous earth or talc. Such granules contain 1 to 50 parts by weight of the active ingredient. The herbicide of the present invention can be applied to various harmful weeds, including typical harmful grasses such as Japanese field grass, Japanese cypress, and Japanese chickweed, which are known to be harmful to rice fields, and representative harmful grasses such as A. japonica and Japanese chickweed, which are known to be harmful to upland fields. Shows herbicidal activity against. Furthermore, no chemical damage to rice or soybeans is observed. Next, the herbicide of the present invention will be explained using formulation examples and test examples. Specific examples for the preparation of the agent of the present invention are shown below. Note that "parts" means "parts by weight." Example 1 (Emulsion) Compound No. 3 25 parts xylene 35 parts cyclohexanone 30 parts Sorbol 800A 10 parts (trademark of Toho Chemical Co., Ltd.) were uniformly mixed and dissolved to obtain an emulsion of the present invention. Example 2 (Wettable powder) Compound No.-28 50 parts Kaolin clay 45 parts Sorbol 5039 5 parts were mixed and ground to obtain a wettable powder of the present invention. Example 3 (Powder) 5 parts of Compound No. 11 and 95 parts of kaolin clay were mixed and ground to obtain a powder of the present invention. Example 4 (Granules) Compound No.-1 5 parts Bentonite 45 parts Talc 45 parts Sodium ligninsulfonate 5 parts were uniformly mixed and ground, water was added, kneaded, and granulated and dried to obtain granules of the present invention. . Next, the usefulness of the compounds according to the present invention will be specifically explained in the following test examples. Test Example 1 (Paddy soil treatment) Paddy soil was filled in a pot with a diameter of 11.5 cm and a depth of 10 cm, and after adding paddy soil containing various paddy weeds to the surface layer, fertilization was applied, plowing was performed, and the water was flooded to 3 cm. : Nihonbare, leaf age 2.5 leaf stage) Two plants were transplanted.
On the fourth day after transplanting the paddy rice, a predetermined amount of the diluted solution of the present invention agent with water was dropped into the water using a pipette. The investigation was carried out by observing the herbicidal effect and the presence or absence of chemical damage to paddy rice on the 20th day after chemical treatment. The results are shown in Table 2. The evaluation in the table is based on the following criteria. Herbicidal effect index Herbicidal damage index 5: Complete herbicidal effect -: Harmless 4: 80-90% herbicidal effect ±: Slightly harmful 3: Herbicidal effect of 60-79% 〓: Minor damage 2: Herbicidal effect of 40-59% 〓 : Severe damage 1: Weeding effect of 20-39% 〓: Severe damage 0: Weeding effect of 20% or less Soybean seeds were sown, and the soil was covered with 2 cm of field soil mixed with crabgrass and blueberry seeds, and then watered uniformly. On the day after sowing, a predetermined amount of a solution of the present invention agent diluted with water was applied uniformly to the soil surface. The investigation was carried out by observing the chemical damage to soybeans and the herbicidal effect on various weeds on the 20th day after chemical treatment. The results are shown in Table 2. The evaluations in the table were conducted according to the standards of Test Example 1. Example 3 (Stem and leaf treatment) Field soil was filled in clay pots with a diameter of 11.5 cm and a depth of 11 cm, field soil containing weed seeds such as crabgrass and blueberry was added to the surface layer, and the plants were grown and managed in a glass greenhouse. When there were 2 to 3 leaves of the crabgrass and 1 to 2 true leaves of the bluegrass, a solution of the present invention diluted with water at a predetermined concentration was sprayed at an amount of 10 per are. The investigation was conducted by observing the effects on each weed 14 days after chemical treatment. The evaluations in the table were conducted according to the standards of Test Example 1.
The results are shown in Table 2.

【table】

【table】

Claims (1)

[Claims] 1. General formula [However, in the formula, X is a hydrogen atom, a halogen atom,
Represents a lower alkyl group, lower alkoxy group, trifluoromethyl group or nitro group. n is 1 to 3
and when n is 2 or 3, X may be the same or different from each other. ] A metabenzyloxybenzoic acid amide derivative represented by 2 General formula [However, in the formula, X is a hydrogen atom, a halogen atom,
Represents a lower alkyl group, lower alkoxy group, trifluoromethyl group or nitro group. n is 1 to 3
and when n is 2 or 3, X may be the same or different from each other. ] A herbicide containing a metabenzyloxybenzoic acid amide derivative represented by: