JP2570343B2 - Carbamate derivative - Google Patents

Description

The present invention relates to a carbamate derivative, a method for producing the same, and a herbicide characterized by containing the compound as an active ingredient.

[Prior art] Isopropyl N- (3) is used as a carbamate herbicide.
-Chlorophenyl) carbamate and methyl N- (3,4
(Dichlorophenyl) carbamate and the like are known, but the herbicidal action of the selectivity between crops and weeds is not always sufficient, and development of a herbicide having high selectivity has been awaited.

[Problems to be Solved by the Invention] The present inventors have intensively studied to develop a highly selective herbicide with little phytotoxicity, and as a result, completed the present invention.

[Means for Solving the Problems] The compound of the present invention selectively kills morning glory, one of the harmful weeds, among field weeds, and is highly sensitive to carbamate herbicides as well as wheat and soybeans. It has the characteristic that it does not show chemical damage to radish.

That is, the present invention relates to (1) the general formula (I) (Wherein X represents an oxygen atom or a sulfur atom, and R ¹ and R ² represent a lower alkyl group, a phenyl group optionally substituted with a lower alkyl group or a halogen atom, or a lower alkyl group, a lower alkoxy group or a halogen atom. And R ¹ and R ² may form a heterocyclic group together with the nitrogen atom to which they are bonded.) (2) General formula (II) And a general formula (III): (In the formula, X represents an oxygen atom or a sulfur atom, Y represents a halogen atom, and R ¹ and R ² represent a lower alkyl group, a phenyl group which may be substituted with a lower alkyl group or a halogen atom, or a lower alkyl group. Represents a pyridyl group which may be substituted with a lower alkoxy group or a halogen atom,
R ¹ and R ² may form a heterocyclic group together with the nitrogen atom to which R ¹ and R ² are bonded.) A carbamoyl halide represented by the general formula (I): (Wherein X represents an oxygen atom or a sulfur atom, and R ¹ and R ² represent a lower alkyl group, a phenyl group optionally substituted with a lower alkyl group or a halogen atom, or a lower alkyl group, a lower alkoxy group or a halogen atom. Wherein R ¹ and R ² may form a heterocyclic group together with the nitrogen atom to which they are bonded, and (3) a carbamate derivative represented by the following general formula (I) ): (In the formula, X represents an oxygen atom or a sulfur atom, and R ¹ and R ² represent a lower alkyl group, a phenyl group optionally substituted with a lower alkyl group or a halogen atom, or a lower alkyl group, a lower alkoxy group, or a halogen atom. A pyridyl group which may be substituted by an atom, wherein R ¹ and R ² may form a heterocyclic group together with the nitrogen atom to which they are bonded.) Is provided.

[Operation] Hereinafter, the present invention will be described in more detail.

The compound of the general formula (I) of the present invention is a novel compound which has not been described in the literature. Examples of these compounds include the following.

N-oxy-3-pyridyl N, N-dimethylcarbamate, N-oxy-3-pyridyl N, N-diethylcarbamate, N-oxy-3-pyridyl N, N-dipropylcarbamate, N-oxy-3-pyridyl N, N-di (1-methylethyl) carbamate, N-oxy-3-
Pyridyl N, N-dibutyl carbamate, N-oxy-
3-pyridyl N-methyl-N-phenylcarbamate, N-oxy-3-pyridyl N-methyl-N- (2
-Methylphenyl) carbamate, N-oxy-3-pyridyl N-methyl-N- (3-methylphenyl) carbamate, N-oxy-3-pyridyl N-ethyl-N
-(4-methylphenyl) carbamate, N-oxy-
3-pyridyl N- (3,4-dichlorophenyl) -N-
Methyl carbamate, N-oxy-3-pyridyl N-
(3-chlorophenyl) -N-methylcarbamate, N
-Oxy-3-pyridyl N-methyl-N- (2-pyridyl) carbamate, N-oxy-3-pyridyl N-
(6-chloro-2-pyridyl) -N-methylcarbamate, N-oxy-3-pyridyl N- (6-methoxy-
2-pyridyl) -N-methyl carbamate, N-oxy-3-pyridyl N, N-diphenyl carbamate, O-
(N-oxy-3-pyridyl) N, N-dimethylthiocarbamate, O- (N-oxy-3-pyridyl) N, N
-Diethylthiocarbamate, O- (N-oxy-3-
Pyridyl) N-methyl-N-phenylthiocarbamate, O- (N-oxy-3-pyridyl) N-methyl-
N- (3-methylphenyl) thiocarbamate, O-
(N-oxy-3-pyridyl) N-methyl-N- (4
-Methyl-2-pyridyl) thiocarbamate, O- (N
-Oxy-3-pyridyl) N, N-tetramethylenethiocarbamate, N-oxy-3-pyridyl N, N-tetramethylenecarbamate, N-oxy-3-pyridyl
N, N-pentamethylene carbamate The carbamate derivative represented by the general formula (I) of the present invention can be produced according to the following reaction formula.

(Wherein, X represents an oxygen atom or a sulfur atom, Y represents a halogen atom, and R ¹ and R ² represent a lower alkyl group, a phenyl group optionally substituted with a lower alkyl group or a halogen atom, or a lower alkyl group. , A lower alkoxy group or a pyridyl group which may be substituted with a halogen atom,
R ¹ and R ² may form a heterocyclic group together with the nitrogen atom to which they are bonded.) The above reaction is usually carried out in the presence of a dehydrohalogenating agent and further in the presence or absence of a reaction solvent. From 0 ° C
The reaction proceeds at a reaction temperature of 150 ° C., and the reaction time is about several minutes to 48 hours.

Examples of the dehydrohalogenating agent include alkali hydroxides such as sodium hydroxide and potassium hydroxide, alkaline earth hydroxides such as calcium hydroxide, and alkali carbonates such as sodium carbonate, potassium carbonate, sodium hydrogen carbonate and potassium hydrogen carbonate. And hydrides such as sodium hydride, and tertiary amines such as triethylamine, dimethylaniline and pyridine.

Examples of the reaction solvent include water and alcohols such as methanol, ethanol and isopropanol, ketones such as acetone and methyl ethyl ketone, benzene, toluene, and the like.
Aromatic hydrocarbons such as xylene, ethers such as ethyl ether, tetrahydrofuran, and dioxane; halogenated hydrocarbons such as chlorobenzene, chloroform, carbon tetrachloride, and dichloroethane; and polar solvents such as dimethylformamide and dimethylsulfoxide are used. .

The carbamate derivative represented by the general formula (I) of the present invention is obtained by reacting the corresponding pyridinol derivative with phosgene, thiophosgene, trichloromethylchloroformate, or the like. (Wherein X represents an oxygen atom or a sulfur atom, and Y represents a halogen atom), and a general formula (V): (R ¹ and R ² represent a lower alkyl group, a lower alkyl group or a phenyl group optionally substituted with a halogen atom, or a lower alkyl group, a lower alkoxy group or a pyridyl group optionally substituted with a halogen atom; ¹ and R ² may form a heterocyclic group together with the nitrogen atom to which they are bonded.)

When the compound of the present invention is used as a herbicide, an appropriate amount of one or more of the compounds represented by the above general formula (I) is mixed with an inert carrier, and the wettable powder is used in a usual agricultural chemical use form. It is used in the form of emulsions, aqueous solvents, flowables, powders, etc.

Solid carriers include talc, clay, diatomaceous earth, bentonite, kaolin, acid clay, white carbon,
Examples of the liquid carrier include water, alcohol, benzene, toluene, xylene, kerosene, cyclohexane, cyclohexanone, isophorone, ethylene glycol monobutyl ether, benzyl acetate, dimethylformamide, and mineral oil.

Further, if necessary in the preparation, a surfactant, a stabilizer and the like can be added. Further, the herbicide of the present invention can be used in combination with other pesticides used in the same field, for example, insecticides, fungicides, herbicides, plant growth regulators or fertilizers. In particular, it may be appropriate to add and mix other herbicides for the purpose of reducing spraying labor or for widening the range of grass species that can be effectively controlled.

Examples of herbicides that can be added include triazine herbicides such as simazine and atrazine; urea herbicides such as DCMU and linuron; phenoxy herbicides such as 2,4-D, MCP and fluazifopbutyl; Diphenyl ether herbicides such as fluorophene; heterocyclic herbicides such as bromacil and bentazone; amide herbicides such as propanil and arachlor; dinitroaniline herbicides such as trifluralin and pendimethalin; and nitriles such as ioxynil and bromoxynil. And the like.

A successful combination of one or two of these herbicides can provide an effective admixture for many grass species.

The compound of the present invention shows a high herbicidal activity particularly to morning glory. The application dose of the compound of the present invention depends on the application scene, application time,
Although it varies depending on the application method, target plant species, and the like, the amount of the active ingredient is generally in the range of 50 to 1000 g / 10a, preferably 100 to 500 g / 10a.

[Examples] Next, the present invention will be described in more detail by way of examples, but the present invention is not limited to only these examples.

Example 1 N-oxy-3-pyridyl N- (6-methoxy-2-
Method for producing pyridyl) -N-methylcarbamate (Compound No. 1 of the present invention) 2.1 g of N- (6-methoxy-2-pyridyl) -N-methylcarbamoyl chloride, 3-hydroxypyridine-
1.1 g of N-oxide and 1.5 g of anhydrous potassium carbonate were added to 20 ml of acetone, and the mixture was heated under reflux for 24 hours.

After cooling the reaction mixture to room temperature, the precipitate was filtered and acetone was distilled off under reduced pressure. The residue was subjected to column chromatography (silica gel, chloroform / methanol = 9 /
Purified by N-oxy-3-pyridyl N
1.5 g (53% yield) of-(6-methoxy-2-pyridyl) -N-methyl carbamate was obtained. (Mp 155 to 157 ° C.) Next, typical examples of the compound of the present invention represented by the above general formula (I) and physical properties thereof are shown in Table 1 below.

Next, examples of specific formulations using the compound of the present invention will be described. In the examples, "parts" are parts by weight.

Example 2 (Emulsion) 80 parts of benzene and 10 parts of Solpol 800A as a surfactant were mixed and dissolved in 4,10 parts of the compound of the present invention to obtain a 10% emulsion.

Next, the herbicidal effect of the compound of the present invention will be described with reference to Examples and Comparative Examples.

Example 3 10 parts of the compound of the present invention or a comparative compound as a carrier material, 87.7 parts of Ziglite [trade name, manufactured by Kunimine Kogyo Co., Ltd.], and 1.35 parts of Neoperex [trade name, manufactured by Kao Atlas Co., Ltd.] as a surfactant. And 1.35 parts of Solpol 800A (trade name, manufactured by Toho Chemical Industry Co., Ltd.) to obtain a 10% wettable powder.

Field soil was placed in a porcelain pot with a diameter of 12 cm. Noasaagao and seeds of radish, soybean, and wheat were sown on the soil surface layer and covered lightly. Growing in greenhouse, Noasaagao true leaves 2
At the time of developing, a predetermined amount of the wettable powder of the compound of the present invention and the comparative compound prepared as described above was diluted with 2 ml of water per pot and sprayed with foliage. For three days after the treatment, watering of foliage was avoided. Two weeks after the chemical treatment, the herbicidal effect and the phytotoxicity were examined by observation.

The evaluation of the herbicidal effect and the phytotoxicity was made according to the following criteria, and the results are shown in Table 2.

Criterion for judging herbicidal effect Judgment criteria for harmful effect Labeling Herbicidal effect indication Chemical harm 5: 100% control 0: Harmless 4: 80% control 1: Minor harm 3: 60% control 2: Minor harm 2: 40% control 3: Moderate harm 1 : 20% control 4: severe harm 0: 0% control 5: severe harm to death [Effects of the invention] As is clear from Table 2, the compound of the present invention exhibits a particularly excellent herbicidal action against morning glory, which is one of the severely harmful weeds, and has a high selection that it does not show any phytotoxicity to crops. It is a herbicide having properties.

Claims (3)

(57) [Claims] 1. A compound of the general formula (I): (Wherein X represents an oxygen atom or a sulfur atom, and R ¹ , R
² represents a lower alkyl group, a phenyl group optionally substituted with a lower alkyl group or a halogen atom, or a pyridyl group optionally substituted with a lower alkyl group, a lower alkoxy group, or a halogen atom, and R ¹ and R ² May form a heterocyclic group together with the nitrogen atom to which it is bonded). 2. The general formula (II): And a pyridinol derivative represented by the general formula (III): (Wherein, X represents an oxygen atom or a sulfur atom, Y represents a halogen atom, and R ¹ and R ² represent a lower alkyl group, a phenyl group optionally substituted with a lower alkyl group or a halogen atom, or a lower alkyl group. Represents a pyridyl group which may be substituted with a halogen group, a lower alkoxy group or a halogen atom, wherein R ¹ and R ² may form a heterocyclic group together with the nitrogen atom to which they are bonded.) General formula (I) characterized in that: (Wherein X represents an oxygen atom or a sulfur atom, and R ¹ , R
² represents a lower alkyl group, a phenyl group optionally substituted with a lower alkyl group or a halogen atom, or a pyridyl group optionally substituted with a lower alkyl group, a lower alkoxy group, or a halogen atom, and R ¹ and R ² May form a heterocyclic group together with the nitrogen atom to which it is bonded)). 3. A compound of the general formula (I): (Wherein X represents an oxygen atom or a sulfur atom, and R ¹ , R
² represents a lower alkyl group, a phenyl group optionally substituted with a lower alkyl group or a halogen atom, or a pyridyl group optionally substituted with a lower alkyl group, a lower alkoxy group, or a halogen atom, and R ¹ and R ² May form a heterocyclic group together with the nitrogen atom to which it is bonded).