JP2597212B2 - Benzylideneaminooxyalkanoic acid thioamide derivatives, their production and herbicides - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a novel benzylideneaminooxyalkanoic acid thioamide derivative, a method for producing the same, and a herbicide containing the same as an active ingredient.

[Conventional technology]

Heretofore, it has been known that phenoxyalkanoic acid amide derivatives exhibit herbicidal activity, but it is not known that the benzylideneaminooxyalkanoic acid thioamide derivative of the present invention exhibits herbicidal activity.

[Problems to be solved by the invention]

An object of the present invention is to provide a novel benzylideneaminooxyalkanoic acid thioamide derivative, a method for producing the same, and a herbicide containing the same as an active ingredient.

[Means for solving the problem]

The present inventors have conducted intensive studies to solve the above problems, and as a result, a novel benzylideneaminooxyalkanoic acid thioamide derivative has a wide range of herbicidal effects on grasses and broadleaf weeds. It was found that weeds that are difficult to weed show a high herbicidal effect, and that they also show a highly selective herbicidal effect that seedlings, rice, wheat, soybeans, corn, and the like have no phytotoxicity. Reached.

That is, the present invention provides: (Wherein, R ₁ represents a halogen atom, a halo-lower alkyl group, a halo-lower alkoxy group, a phenyl group optionally substituted with a cyano group or a nitro group; R ₂ represents a lower alkyl group; R ₃ represents a halogen atom A phenyl group which may be substituted with an atom, or a thienyl group which may be substituted; n represents 0 or 1); benzylideneaminooxyalkanoic acid thioamide derivative represented by the following formula: : (Wherein R ₁ , R ₂ , R ₃ and n have the same meanings as described above). A compound represented by the formula (I): (3) a method for producing a benzylideneaminooxyalkanoic acid thioamide derivative represented by the formula (I);

 Hereinafter, the present invention will be described in detail.

In the above-mentioned target compound, the novel benzylideneaminooxyalkanoic acid thioamide derivative (I) and the compound of the raw material for producing the same (II), R ₁ may be a phenyl group which may be substituted, Examples of a thienyl group and an optionally substituted furyl group include a phenyl group which may be substituted; a halogen atom (for example, a chlorine atom,
A bromine atom, a fluorine atom, an iodine atom, etc., a halo-lower alkyl group (e.g., trifluoromethyl, difluoromethyl, 1,1-difluoroethyl, 1,1,2,2-tetrafluoroethyl, pentafluoromethyl, etc.), Halo-lower alkoxy group (for example, difluoromethoxy, trifluoromethoxy, 1,1,2-trifluoro-2-chloroethoxy, etc.), cyano group, nitro group, lower alkyl group, lower alkoxy group, halo-lower alkylthio group, halo Although a lower alkylsulfonyl group and the like can be mentioned, a halogen atom, a halo-lower alkyl group, a halo-lower alkoxy group, a cyano group, a nitro group and the like are preferable (more preferably, a halogen atom is preferably a fluorine atom, As an alkyl group, a trifluoromethyl group is preferred, and as a halo-lower alkoxy group, Difluoromethyl group, good trifluoromethyl group. Further, more preferably from position even 3-position of any substituent).

R ₂ may be a linear or branched alkyl group having 1 to 6 carbon atoms, preferably an alkyl group having 1 to 4 carbon atoms (more preferably an ethyl group). .

Examples of R ₃ include a phenyl group which may be substituted, a thienyl group which may be substituted, a furyl group which may be substituted, a cycloalkyl group which may be substituted, and the like. Is preferably a phenyl group which may be substituted, a thienyl group which may be substituted, and the like; examples of the substituent in the phenyl group include a halogen atom (for example, a chlorine atom, a bromine atom, a fluorine atom, an iodine atom, etc.), Examples thereof include a lower alkyl group, a halo-lower alkyl group, and a lower alkoxy group, preferably a halogen atom (more preferably a chlorine atom or a fluorine atom, and more preferably the position of any of the substituents. 2nd and / or 4th is better).

 n represents 0 or 1.

Examples of the thiocarbonylating agent include phosphorus pentasulfide and phosphorus sulfide such as Lawesson's reagent, but phosphorus pentasulfide is preferred.

The novel benzylideneaminooxyalkanoic acid thioamide derivative (I) as the target compound also includes optical isomers based on asymmetric carbon atoms.

The target compound (I) of the present invention can be produced, for example, by the following method.

(In the formula, R ₁ , R ₂ , R ₃ and n have the same meanings as described above.) The target compound (I) is usually prepared by reacting the starting compound (II) with a thiocarbonylating agent in a solvent. Can be manufactured.

The starting compound (II) used in the present invention can be easily produced, for example, by the method shown by the following formula.

(Wherein, R ₁ , R ₂ and R ₃ have the same meanings as above; X represents a halogen atom.) The solvent is not particularly limited as long as it does not directly participate in the reaction. Chlorinated or unchlorinated aromatic or aliphatic hydrocarbons such as toluene, xylene, methylnaphthalene, chlorobenzene, dichlorobenzene, methylene chloride, chloroform, dichloroethane; diethyl ether, tetrahydrofuran,
Ethers such as dioxane; and mixtures of the above-mentioned solvents.

The target compound (I) can be produced at a reaction concentration of 5 to 60%.

In the production method, the ratio of using the starting compound (II) and the thiocarbonylating agent can be 1 to 3 moles of the thiocarbonylating agent per 1 mole of the starting compound (II). Is preferably 1.2 to 2.0 mol.

The reaction temperature is not particularly limited as long as the reaction is carried out at a temperature equal to or lower than the boiling point of the solvent used.
140 ° C is good. ), And it is preferable to shorten the reaction time by heating.

The reaction time varies depending on the above-mentioned concentration and temperature, but can usually be carried out for 0.5 to 12 hours.

The target compound (I) of the present invention is a grass weed (for example,
Nobier, Susenometabira, Meishishiba, etc., as well as general broadleaf weeds (for example, Shiroza, Suberihyu, Rigidsis, Inubiju, Hakobe, etc.) as well as difficult-to-control broadleaf weeds (for example, Ebisugusa, Ichibi, Yaegura, Ooinuguri, Onamimomi, etc.) It shows an excellent herbicidal effect,
Further, the present invention also shows a highly selective herbicidal effect in which seedlings, rice, wheat, soybean, corn and the like have no phytotoxicity.

The herbicide of the present invention contains at least one compound (I) as an active ingredient.

The compound (I) can be used alone, but it is usually compounded with a carrier, a surfactant, a dispersant, an auxiliary agent and the like (for example, a powder, an emulsion, a fine granule, a granule, a hydrate) by an ordinary method. Agent, oily suspension, aerosol, etc.).

Examples of the carrier include solid carriers such as talc, bentonite, clay, kaolin, diatomaceous earth, white carbon, vermiculite, dolomite, zeolite, slaked lime, silica sand, silicic anhydride, ammonium sulfate, urea, wood flour, starch, and cellulose; Hydrocarbons (kerosene, mineral oil, etc.), aromatic hydrocarbons (benzene, toluene, xylene, etc.),
Chlorinated hydrocarbons (chloroform, carbon tetrachloride, etc.), ethers (dioxane, tetrahydrofuran, etc.), ketones (acetone, cyclohexanone, isophorone, etc.), esters (ethyl acetate, ethylene glycol acetate, dibutyl maleate, etc.), alcohol (E.g., methanol, n-hexanol, ethylene glycol, etc.), polar solvents (e.g., dimethylformamide, dimethylsulfoxide), liquid carriers such as water; gaseous carriers such as air, nitrogen, carbon dioxide, freon (in this case, mixed injection) Can be done).

Nonionic, anionic, cationic, and zwitterionic surfactants can be used to improve the performance of this agent, such as adhesion to plants, improvement in absorption, dispersion, emulsification, and spreading of drugs. Surfactants such as alcoholic sulfates, alkyl sulfonates, lignin sulfonates, and polyoxyethylene glycol ethers. In order to improve the properties of the drug, carboxymethylcellulose, polyethylene glycol, gum arabic and the like can be used as an auxiliary.

In the production of this agent, the carrier, surfactant, dispersant,
In addition to auxiliary agents, other pesticides (such as fungicides and insecticides), fertilizers, soil conditioners, and the like can be used alone or in appropriate combination according to the respective purposes.

When the compound (I) of the present invention is formulated, the concentration of the active ingredient is usually 1 to 50% by weight in an emulsion, and usually 0.3 to 2% in a powder.
5% by weight, usually 1-90% by weight for wettable powders, usually for granules
It is usually 0.5 to 5% by weight, usually 0.5 to 5% by weight for oils and 0.1 to 5% by weight for aerosols.

These preparations can be diluted to an appropriate concentration and applied to various uses by spraying them on the foliage of plants, soil, or the water surface of paddy fields, or directly applying them, depending on the purpose.

〔Example〕

Hereinafter, the present invention will be described by way of examples. Note that these examples do not limit the scope of the present invention.

Example 1 (1) [Synthesis of N- (2-fluorobenzyl) -2- (3-trifluoromethylbenzylideneaminooxy) butanoic acid thioamide (compound 3)] N- (2-fluorobenzyl) -2- ( 3-Trifluoromethylbenzylideneaminooxy) butanoic acid amide (10.0 g, 26.1 mmol) is dissolved in xylene (250 ml), and phosphorus pentasulfide (13.4 g, 30.1 mmol) is added. The mixture was heated and stirred for an hour.

After completion of the reaction, the solvent was distilled off under reduced pressure after removing insolubles, and the obtained residue was subjected to silica gel column chromatography [Wakogel C-200, hexane: ethyl acetate = (1
9: 1) to (7: 3) elution. 6.55 g of the target compound (I) (shown as compound 3 in Table 1).
Obtained.

(2) [Synthesis of N- (2-chlorobenzyl) -2- (3-trifluoromethoxybenzylideneaminooxy) butanoic acid thioamide (compound 8)] N- (2-chlorobenzyl) -2- (3-triamide Fluoromethylbenzylideneaminooxy) butanoic acid amide (4.2 g, 10.1 mmol) was dissolved in THF (200 ml), Lawson's reagent (5.0 g, 12.3 mmol) was added, and the mixture was heated and stirred at 40 ° C. for about 1 hour.

After completion of the reaction, the solvent was distilled off under reduced pressure after removing insolubles, and the obtained residue was subjected to silica gel column chromatography [Wakogel C-200, hexane: ethyl acetate = (1
9: 1) to (7: 3) elution. And 3.9 g of the target compound (I) (shown as compound 8 in Table 1) was obtained.

(3) [Synthesis of N- (2-chlorobenzyl) -2- (3-cyanobenzylideneaminooxy) butanoic acid thioamide (compound 11)] N- (2-chlorobenzyl) -2- (3-cyanobenzylideneamino Oxy) butanoic acid amide (4.98 g, 14.0 m
mol) was dissolved in 1,2-dichloroethane (100 ml), phosphorus pentasulfide (8.10 g, 18.2 mmol) was added, and the mixture was heated and stirred at 50 to 60 ° C. for about 1 hour.

After completion of the reaction, the solvent was distilled off under reduced pressure after removing insolubles, and the obtained residue was subjected to silica gel column chromatography [Wakogel C-200, hexane: ethyl acetate = (1
9: 1) to (7: 3) elution. 48.5 g of the target compound (I) (shown as compound II in Table 1).
Obtained.

(4) [Compounds 1, 2, 4, 5 to 7, 9, 1 in Table 1]
Synthesis of 0 and 12] In the same manner as in (1) to (3), the starting compound (II) having substituents (R ₁ , R ₂ , R ₃ and n) as shown in Table ₁ ) And a thiocarbonylating agent to give the desired compound (I) (in Table 1, compounds 1, 2, 4, 5 to 7,
These are shown as 9, 10, and 12, respectively. ) Was able to get.

Table 1 shows the target compound (I) obtained as described above.

Example 2 (1) [Preparation of granule] 8 parts by weight of compound 2, 30 parts by weight of bentonite, talc
59 parts by weight, 1 part by weight of Neoperex powder (trade name; manufactured by Kao Atlas) and 2 parts by weight of sodium ligninsulfonate are uniformly mixed, and then a small amount of water is added and kneaded, then granulated and dried. Granules were obtained.

(2) [Preparation of wettable powder] 50 parts by weight of compound 3, 48 parts by weight of kaolin, and 2 parts by weight of Neoperex powder (trade name, manufactured by Kao Atlas) are uniformly mixed, and then pulverized to obtain a wettable powder. Obtained.

(3) [Preparation of emulsion] 30 parts by weight of compound 12, 60 parts by weight of xylene, 5 parts by weight of dimethylformamide and 5 parts by weight of toxanone (trade name; manufactured by Sanyo Chemical Industries, Ltd.) were added, mixed and dissolved uniformly. An emulsion was obtained.

(4) [Preparation of emulsion] 5 parts by weight of compound 7, 50 parts by weight of talc and 45 parts of kaolin
The parts by weight were uniformly mixed to obtain a powder.

Example 3 (1) [Paddy weeding test] A 1/5000 arel Wagner pot was filled with Ube soil (alluvial clay loam), and then nobie, konagi, pine bye, firefly,
Seeds or tubers such as rice were planted, and water was added to a depth of 3 cm.

The wettable powder of the target compound (I) shown in Table 1 prepared according to Example 2 was diluted with water containing a surfactant (0.05%), and at the time of the first leaf leaping, The compound (I) was dropped using a pipette so that the organic concentration of the compound (I) became 20 g / a. And after controlling for 3 weeks in a glass room with an average temperature of 25 ° C., their weed effect was investigated.

In addition, the evaluation of the drug effect was performed in 6 stages [0: harmless (normal development), 1: slight harm, 2: minor harm,
3: Severe damage, 4: Great harm, 5: Complete withering).

(2) [Upland soil treatment test] A 1/5000 arel Wagner pot was filled with Ube soil (alluvial clay loam), and crabgrass, nobie, shiroza, inubiyu,
Seeds or tubers of Shiroza, Purslane, Rye, soybean, corn, wheat, etc. were planted and covered with soil.

The wettable powder of the target compound (I) shown in Table 1 prepared according to Example 2 was diluted with water containing a surfactant (0.05%), and the compound (I) was effectively used in each of these chemical solutions. Each soil surface was sprayed uniformly so that the concentration became 20 g / a.
After three weeks of management in a glass room at an average temperature of 25 ° C., their herbicidal effects were investigated.

Table 3 shows the results. In addition, the evaluation of the weeding effect
Performed in the same manner as (1).

(3) [Field crop foliage treatment test] Fill a volcano ash soil into a 1/5000 arel Wagner pot, and add crabgrass, nobie, onamimi, oinoufuguri,
The seeds and tubers of chickweed and wheat were planted, covered with soil, and grown for 2 weeks.

A wettable powder of the target compound (I) shown in Table 1 prepared according to Example 2 was washed with water containing a surfactant (0.05%) in water.
It was diluted to 00 ppm and sprayed uniformly on each of the above plants. And after managing for 3 weeks in a glass room with an average temperature of 25 ° C,
Their herbicidal effects were investigated.

Table 4 shows the results. The evaluation of the herbicidal effect was performed in the same manner as in (1).

(Effect of the Invention) The novel benzylideneaminooxyalkanoic acid thioamide derivative of the present invention exhibits an excellent herbicidal effect on grasses, general broadleaf weeds, and difficult-to-control broadleaf weeds, and furthermore, seedling rice, wheat, It also shows a highly selective herbicidal effect with no phytotoxicity to soybeans and corn.

Claims (3)

(57) [Claims] 1. The following formula: (Wherein, R ₁ represents a halogen atom, a halo-lower alkyl group, a halo-lower alkoxy group, a phenyl group optionally substituted with a cyano group or a nitro group; R ₂ represents a lower alkyl group; R ₃ represents a halogen atom A phenylidyl group which may be substituted by an atom, or a thienyl group which may be substituted; n represents 0 or 1). 2. The following formula: (Wherein R ₁ , R ₂ , R ₃ and n have the same meanings as described in claim 1). A compound represented by the formula (I) is reacted with a thiocarbonylation reactant. A process for producing a benzylideneaminooxyalkanoic acid thioamide derivative represented by the formula (I). 3. A herbicide comprising, as an active ingredient, a thioamino acid derivative of benzylideneaminooxyalkanoate represented by the formula (I) according to claim 1.