JPS63264583A - Pyridyl-2-oxy-phenoxypropionic acid derivative - Google Patents

Abstract

NEW MATERIAL:A compound expressed by formula I (X is H or Cl; R1 is H or methyl; R2 is 1-4C alkyl). EXAMPLE:(3-Methyl-1,2,4-oxadiazo-5-yl)methyl 2-[4-(3-chloro-5-trifluoromethyl-2- pyridyloxy)-phenoxy]propionate. USE:A selective herbicide. PREPARATION:A phenoxypropionic acid expressed by formula II {e.g. 2-[4-(3- chloro-5-trifluoromethyl-2-pyridyloxy)-phenoxy]propionic acid} is reacted with an oxadiazole halide expressed by formula III (Hal is halogen) (e.g. 3-methyl-5- chloromethyl-1,2,4-oxadiazole), as necessary, in the presence of a reaction solvent, preferably at 20-100 deg.C for several min-48hr.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a novel pyridyl-2-oxy-phenoxypropionic acid derivative, a method for producing the same, and a selective herbicide containing the compound as an active ingredient.

[Conventional technology]

It has been reported that many phenoxypropionate derivatives have herbicidal activity.

For example, 2-C4-(4-4lifluoromethylphenoxy)phenoxyfupropionic acid methyl ester, 2-
C4-(2,4-dichlorophenoxy)phenoxy]methyl esternope propionate 2-[:4-(3,5-dichloro-2-pyridyloxy)phenoxy]methyl ester propionate 2-C4-(5- )! J fluoromethyl-2-pyridyloxy)phenoxypropionate butyl ester and the like are known and used for weed control. However, the effectiveness of these substances is not always sufficient.

[Problem that the invention seeks to solve]

Beet, soybean, cotton, alfalfa, rapeseed, potato,
In the cultivation of broad-leaved crops such as sunflowers, radish, Chinese cabbage, cabbage, and tomatoes, without harming these useful crops,
There is still a strong market demand for a selective herbicide that can kill regular weeds using either pre-emergence soil treatment or post-emergence foliage treatment, even though many herbicides have already been developed and sold. . In particular, when foliage treatment is performed after weed emergence, the conventional phenoxypropionate esters described above take more than 8 days to achieve post-treatment effects, which has caused many dissatisfaction among crop growers. It was strongly desired.

The object of the present invention is to obtain said compounds industrially and to provide even more improved selective herbicides that meet the demands of the market.

[Means and effects for solving the problems] The present invention is based on the general formula (I) (wherein, X represents a hydrogen atom or a chlorine atom, R4 represents a hydrogen atom or a methyl group, and R2 represents a carbon atom of 1 to 4 The present invention provides novel pyridyl-2-oxy-phenoxy, propionic acid derivatives (hereinafter referred to as the compounds of the present invention) represented by the following alkyl groups, a method for producing the same, and a herbicide containing the same as an active ingredient.

The present invention will be explained in detail below.

The compound of the present invention can be produced by various methods, but
Three typical manufacturing methods are shown in the following reaction formulas. However, in the formula, XSR and R2 represent the same meanings as above, and Hal
represents a halogen atom.

These reactions are carried out in the presence or absence of a reaction solvent.
The compounds of the present invention are obtained by using a suitable base.

Examples of reaction solvents include ketones such as acetone and methyl ethyl ketone, aromatic hydrocarbons such as benzene, toluene, and xylene, nitrogen compounds such as ethyl ether, tetrahydrofuran, and dioxane, and chlorobenzene, chloroform, carbon tetrachloride, and dichloroethane. Used are halogenated hydrocarbons, tertiary amines such as triethylamine, pyridine, and dimethylaniline, and polar solvents such as acetonitrile, dimethylformamide, dimethyl sulfoxide, and hexamethyltriamide phosphate.

As a base, triethylamine, pyridine, 1.8-
diazabicyclo-(5,4,0)-7-undecene,
Tertiary amines such as dimethylaniline, hydroxide) IJ
alkali hydroxides such as aluminum, potassium hydroxide, alkaline earth hydroxides such as calcium hydroxide, alkali carbonates such as sodium carbonate, potassium carbonate, sodium hydrogen carbonate, potassium hydrogen carbonate, and metal hydrides such as sodium hydride. etc. are used. The reaction usually takes place at a temperature of about 150°C to about 150°C.
, preferably at a reaction temperature of about 0° C. to about 100° C., and the reaction time ranges from several minutes to about 48 V! It is about between tf.

Representative examples of the compounds of the present invention are shown in Table 1 below, but the present invention is not limited only to these compounds.

Table 1 I Cji! HCH3n”1.5
2502 HCH, C)1. n25
1.50903 C,! C
H, C113 mouth 251.61505 Cj!
C) I3n-C3H,'n251.50866
C1l CH31-CJ, n251.
50407 C1l CL n
7C,)I, n” 1.51088
0β [:L t-CJs mouth 25
1.50749 CJ2 HHn2
51.5255 When the compound of the present invention is used as a herbicide, it can be prepared by using a pesticide auxiliary and a method commonly used in pesticide formulations, such as emulsions, wettable powders, aqueous solutions, oil solutions, etc.
It can be used in the form of preparations such as powders and granules.

In actual use, these various preparations can be used as they are or diluted with water to a predetermined concentration.

Specific examples of pesticide adjuvants include diluents, surfactants, stabilizers, sticking agents, aerosol propellants, and synergists. Solvents used as diluents include water, organic solvents, hydrocarbons, halogenated hydrocarbons, alcohols, ethers, alcohol ethers, ketones,
Examples include esters, amides, and sulfoxides.

In addition, fillers and solid carriers include inorganic powder and granules such as slaked lime, magnesium lime, gypsum, calcium carbonate, sand, perlite, pumice, diatomaceous earth, alumina, zeolite,
Examples include clay minerals (talc, vermiculite, kaolinite), vegetable powder (for example, starch, grain, glucose, etc.), synthetic resin powder (for example, phenol resin, carbon resin, vinyl chloride resin), and the like. Examples of surfactants include anionic surfactants (e.g. alkyl sulfates, aryl sulfonic acids, succinic acid, polyethylene glycol, alkylaryl ether sulfate salts), cationic surfactants (e.g. alkyl amines,
Examples include polyoxyethylene alkyl amines), nonionic surfactants (for example, polyoxyethisane glycol ethers, polyoxyethylene glycol esters, polyhydric alcohol esters), and amphoteric surfactants. Other examples include stabilizers, fixing agents, efficacy extenders, dispersion stabilizers, and synergists.

The amount of the compound of the present invention used as an active ingredient can be appropriately changed depending on the form of the preparation, the method of application, purpose, timing, weed growth status, etc.

When generally used, the amount is 0.05 to 10 kg/ha, preferably 0.1 to 5 kg/ha.

[Example] Next, the present invention will be specifically explained with reference to Examples, but the present invention is not limited only to these Examples.

Example 1 (3-methyl-1,2,4-oxadiazol-5-yl)
Synthesis of methyl-2-C4-(3-chloro-5-trifluoromethyl-2-pyridyloxy)-phenoxyfupropionic acid ester (compound No. 1) 2-C4-(3-chloro-5-trifluoromethyl -2
-pyridyloxy)-phenoxy]propionic acid 1.8
3 g, 0.8 g of 3-methyl-5-chloromethyl-1,2,4-oxadiazole and 0.8 g of anhydrous potassium carbonate.
Add 3 g to 50 d of acetonitrile and add 1 while stirring.
It was refluxed for 6 hours. After the reaction mixture was cooled, inorganic substances were filtered off, and acetonitrile was distilled off. The residue was purified by column chromatography [silica gel, developed with benzene/ethyl acetate = lO/1 (V/V)], and 1
．． 23 g of target product (n'' 1.5250) was obtained.

Example 2 (3-methyl-1,2,4-oxadiazol-5-yl)
-1-ethyl-2-(4-(3-chloro-5-trifluoromethyl-2-pyridyloxy)-phenoxy)propionic ester (compound no.

3) Synthesis of 2-C4-(3-chloro-5-trifluoromethyl-2
-pyridyloxy)-phenoxy]furopionic acid 1.1
g, 3-methyl-5-(α-chloroethyl)-1,2,
0.44 g of 4-oxadiazole and 0.42 g of anhydrous potassium carbonate. g was added to 50 ml of acetonitrile, and the mixture was refluxed for 16 hours while stirring.

After cooling the reaction mixture and filtering off inorganic substances, acetonitrile was distilled off. The residue was purified by column chromatography [silica gel, benzene/ethyl acetate = 10/1 (
V/V)] to obtain 0.8 g of the target product (n251
．． 6150) was obtained.

Example 3 Preparation of emulsion 20 parts of the present compound Nα3 (parts indicate parts by weight, the same applies hereinafter), 60 parts of xylene, and Tsurpol 2806B.
(Product name: Surfactant manufactured by Toho Chemical Industries) 20 parts were uniformly stirred and mixed to form an emulsion.

Example 4 Production of wettable powder White carbon 10 parts, Zeekrite 65 parts, Tsurupol 5039 (Product name: Surfactant manufactured by Toho Chemical Industries)
5 parts and 20 parts of the present compound No. 5 were mixed and ground to prepare a wettable powder.

Example 5 Stalk and foliage treatment test Fill a 22cm x 16cm plastic vat with field soil, sow a certain amount of soybean, beet, rice, wheat, corn, and oat seeds, and then weeds such as crabgrass, wild grass, knotweed, chickweed, and white locust. Approximately 1 liter of soil containing seeds
It was covered with soil to a thickness of am. When the gramineous plants reached the 3.0 to 3.5 leaf stage, a prescribed chemical was uniformly sprayed on the foliage. The growth condition of the converted weeds was observed 14 days after the chemical treatment, and the results shown in Table 2 were obtained. The numerical value of the degree of growth inhibition was divided into five levels from 5 to 1 (5 indicates complete withering and 1 indicates no effect).

〔Effect of the invention〕

The compound of the present invention has good selectivity for cultivated plants such as beans, cotton, carrot, potato, beet, citrus, mustard, mustard, peanut, radish, tobacco, tomato, cucumber, etc. Weeds, especially weeds of the genus family, such as Japanese millet, crabgrass, blackberry, etc.
When pre-emergence soil treatment and post-emergence foliage treatment are applied to foxtail grass, wild oat, sparrow gnome, goldenrod, grasshopper, staghorn grass, japonica grass, johnson grass, etc., excellent selective control effects are shown.

Claims (3)

[Claims] (1) General formula [I] ▲Mathematical formula, chemical formula, table, etc.▼[I] (In the formula, X represents a hydrogen atom or a chlorine atom, R_1 represents a hydrogen atom or a methyl group, and R_2 represents a carbon atom from 1 to 4
pyridyl-2-oxy-, which is represented by
Phenoxypropionic acid derivative. (2) General formula [II] ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼ [II] (In the formula, X represents a hydrogen atom or a chlorine atom) Phenoxypropionic acid and General formula [III] ▲ Mathematical formula, There are chemical formulas, tables, etc. ▼ [III] (In the formula, R_1 represents a hydrogen atom or a methyl group, and R_2
represents an alkyl group having 1 to 4 carbon atoms, and Hal represents a halogen atom) General formula [I]▲Mathematical formula, chemical formula,
There are tables etc. ▼ [I] (In the formula, X, R_1 and R_2 have the same meanings as above) A method for producing a pyridyl-2-oxy-phenoxypropionic acid derivative. (3) General formula [I] ▲ Numerical formula, chemical formula, table, etc.▼ [II] (In the formula, X represents a hydrogen atom or a chlorine atom, R_1 represents a hydrogen atom or a methyl group, and R_2 represents a carbon atom from 1 to 4
A selective herbicide comprising, as an active ingredient, a pyridyl-2-oxy-phenoxypropionic acid derivative represented by: