JP2611288B2 - Substituted phenylurea derivatives and herbicides containing them as active ingredients - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a novel benzopyranylalkyloxyphenylurea derivative and a herbicide containing the same as an active ingredient.

[Problems to be solved by conventional technology and invention]

Hitherto, it has been known that benzyloxyphenylurea derivatives have herbicidal activity (see JP-A-53-44544). It is also known that phenethyloxyphenylurea derivatives have herbicidal activity (JP-A-53-108947).
Reference). Furthermore, it is also known that benzopyranyloxyphenylurea derivatives have herbicidal activity (see International Publication No. WO 87/00840). However, these compounds have insufficient selectivity for crops or strong herbicidal activity. Chemical substances often have significant differences in the presence, strength, or selectivity of herbicidal activity due to slight modification of the structure, and simply predict the herbicidal activity or selectivity of a new compound based on the similarity of chemical structures. It is difficult.

An object of the present invention is to provide a novel benzopyranylalkyloxyphenylurea derivative having excellent herbicidal activity.

[Means for solving the problem]

That is, the gist of the present invention is represented by the following general formula (I) (In the above formula, A represents an alkylene group, and R ¹ , R ² , R ³ and
R ⁴ each independently represents a hydrogen atom or a methyl group,
R ⁵ represents a methyl group or a methoxy group. ) And a herbicide containing the N'-phenyl-N-methylurea derivative as an active ingredient.

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

The novel compound of the present invention is represented by the above general formula (I). In the general formula (I), A is an alkylene group, specifically,
For _{example, -CH 2 -, - CH 2} CH 2 -, Linear or branched alkylene group such as, preferably _{-CH 2 -, - CH 2 CH} 2 -, or Represents R ¹ , R ² , R ³ and R ⁴ each independently represent a hydrogen atom or a methyl group. R ⁵ represents a methyl group or a methoxy group.

The compound of the present invention represented by the general formula (I) is a novel compound, and can be produced using various raw materials, for example, according to the following reaction formula.

(In the above reaction formula, A, R ¹ , R ² , R ³ , R ⁴ and R ⁵ have the same meanings as described above, and X represents a halogen atom.) The above reaction is carried out without solvent or with acetone, ethyl methyl ketone or the like. Ketones; Aromatic hydrocarbons such as benzene and toluene; Ethers such as diethyl ether and tetrahydrofuran; in solvents such as aprotic polar solvents such as acetonitrile, N, N-dimethylformamide, dimethylsulfoxide and N-methylpyrrolidone , Triethylamine, pyridine, N, N-diethylaniline and the like; or an inorganic base such as sodium carbon and sodium hydroxide in the range of 0 to 150 ° C.

(In the above reaction formula, A, R ¹ , R ² , R ³ , R ⁴ and R ⁵ have the same meanings as described above.) The reaction is carried out without a solvent or with an aromatic compound such as benzene, toluene, xylene and chlorobenzene. Hydrocarbons; acetates such as ethyl acetate and isobutyl acetate; ethers such as diethyl ether, diisopropyl ether, tetrahydrofuran and dioxane; aprotic polar solvents such as N, N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone Ketones such as acetone and ethyl methyl ketone; alcohols such as methanol, ethanol and butanol; and reaction in a solvent such as water or a mixed solvent thereof in a temperature range of -50 to 100 ° C. It is.

In addition, isocyanate (III) which is a raw material of the above reaction
Can be produced from the starting aniline derivative (II) in the reaction formula (I) according to the following reaction formula.

(In the above reaction formula, A, R ¹ , R ² , R ³ and R ⁴ have the same meanings as described above.) In the above reaction, aromatic hydrocarbons such as benzene, toluene, xylene, and chlorobenzene; ethyl acetate; Acetates such as isobutyl acetate; triethylamine in a solvent such as ethers such as diethyl ether, diisopropyl ether, tetrahydrofuran and oxazine;
The reaction is carried out in the presence or absence of an organic base such as pyridine, quinoline and N, N-diethylaniline in a temperature range of -20 to 180 ° C.

(In the above reaction formula, A, R ¹ , R ² , R ³ , R ⁴ and R ⁵ are as defined above, and Y represents a halogen atom, an alkylsulfonyloxy group or an arylsulfonyloxy group.) No solvents or ketones such as acetone and ethyl methyl ketone; aromatic hydrocarbons such as benzene and toluene; ethers such as diethyl ether and tetrahydrofuran; acetonitrile, N, N-dimethylformamide, dimethyl sulfoxide, N-methylpyrrolidone Organic solvents such as triethylamine, pyridine, N, N-diethylaniline; inorganic bases such as sodium carbonate and sodium hydroxide; alkali metal hydrides such as sodium hydride; Temperature of 0 to 150 ° C in the presence or absence of alkali metal such as metallic sodium It is performed in a range.

The aniline derivative (II), which is a reaction raw material in the reaction formulas (1) and (2), can be produced by the following method (a) or (b).

(In the above reaction formula, A, R ¹ , R ² , R ³ , R ⁴ and X are as defined above.) (In the above reaction formula, A, R ¹ , R ² , R ³ , R ⁴ and Y have the same meanings as described above.) The compound of the present invention thus obtained can be used as it is as a herbicide, but is usually inactive. And a suitable liquid carrier or solid carrier, to which an appropriate surfactant or the like is added, and used in the form of emulsions, powders, wettable powders and the like.

As the liquid carrier, toluene, xylene, methylnaphthalene, cyclohexane, butanol, glycol, dimethyl sulfoxide, dimethylformamide, acetone, methyl isobutyl ketone, animal and vegetable oils, fatty acids, fatty acid esters, water, etc., and as the solid carrier, Vegetable powders such as clay, kaolin clay, talc, bentonite, diatomaceous earth, silica, calcium carbonate and soybean flour, wheat flour and the like can be mentioned. If you need more,
It can also be used in admixture with other active ingredients, such as agricultural fungicides, insecticides, nematicides or other herbicides, plant growth regulators, soil conditioners and fertilizers. Further, in order to obtain a reliable herbicidal effect, it is preferable to appropriately mix auxiliary agents such as a spreading agent, an emulsifier, a wetting agent and a fixing agent.

The application rate of the herbicide of the present invention depends on the type of the compound used,
Depending on the target weed, treatment time, treatment method or soil properties, etc.
A range of 0.5-80 grams, preferably 1-50 grams, is suitable.

〔The invention's effect〕

The present inventors have found that the compound of the present invention exhibits high herbicidal activity in upland fields and paddy fields, but hardly affects crops. That is, in the field, for example, Shiroza, Akaza, Inutade, Halade, Inubiyu, Suberihyu, Hakobe, Hotokenoza, Meishishiba, Ohishiba, Enokorogosa, Sparrow Notepopo, Kayatsurigusa, In the paddy field, for example, Azena, Kikashigusa, Abinome, Rabbitus And weeds such as conger can be controlled in any of the pre-emergence treatment and the growing season treatment, and have little effect on crops such as rice, sunflower, potato, wheat, barley, sugarcane, and corn. Therefore, it can be used as a selective herbicide for cultivation of these crops.

As described above, the compound of the present invention has an excellent property that many weeds can be controlled with little harm to crops.

Furthermore, the compound of the present invention is highly effective in controlling weeds that have been difficult to control with existing herbicides, i.e., in fields, such as, for example, Ichibi, Datura Asagao, Wild mustard, Yaemuragra, Western violet, Oroshi-chrysanthemum and the like. It was found to have activity. Thus, the compounds of the present invention have a very broad spectrum of weeds and a high degree of safety against crops.

The application range of the compound of the present invention is not limited to only the above types of plants, and can be used for other plants by the same application method.

〔Example〕

Next, the present invention will be described more specifically with reference to examples, but the present invention is not limited to the following examples unless it exceeds the gist.

Example 1 1- [4-{(3,4-dihydro-2H-1-benzopyran-6-yl) methyloxy} phenyl] -3
-Methoxy-3-methylurea 4-[(3,4-dihydro-2H-1-benzopyran-6
-Yl) methyloxy] aniline (2.6 g) was dissolved in pyridine (15 ml), and N-methoxy-N-methylcarbamoyl chloride (1.5 g) was gradually added dropwise under ice cooling. After stirring at room temperature for 2 hours, the mixture was poured into ice water and extracted with ethyl acetate. The organic layer was washed with diluted hydrochloric acid and saturated saline, and then dried over anhydrous sodium sulfate.

Ethyl acetate was distilled off under reduced pressure, and the residue was recrystallized from cyclohexane to give the compound (No. 1) shown in Table 1
2.9 g were obtained.

Example 2 1- [4-{(3,4-dihydro-2-methyl-2H-1-benzopyran-6-yl) ethyloxy} phenyl] -3,3-dimethylurea 4-([3,4-dihydro 3.1 g of 2-methyl-2H-1-benzopyran-6-yl) ethyloxy] phenylisocyanate was dissolved in 30 ml of toluene, and 0.9 g of dimethylamine dissolved in 5 ml of toluene was gradually added dropwise at room temperature. After stirring at room temperature for 2 hours, toluene was distilled off under reduced pressure, and the residue was recrystallized from ethyl acetate to obtain 2.7 g of the compound (No. 10) shown in Table 1.

Example 3 1- [3- {3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-6-yl) methyloxy} phenyl] -3-methoxy-6-methylurea 1- (3- (Hydroxyphenyl) -3-methoxy-3
-2.0 g of methyl urea in dry N, N-dimethylformamide 20m
and 0.4 g of 60% sodium hydride was added. After stirring for 15 minutes and cooling with ice, 3-[(3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-6-yl] methyl chloride
2.1 g was added dropwise. After stirring at room temperature for 3 hours, the mixture was poured into ice water and extracted with ethyl acetate. The organic layer was washed with water and dried over anhydrous sodium sulfate. Ethyl acetate was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (eluent: n-hexane / ethyl acetate = 3/1) to obtain Table 2.
2.6 g of the described compound (No. 34) was obtained.

Example 4 1- [3-{(3,4-dihydro-2,2-dimethyl-2H-1-benzopyran-6-yl) ethyloxy}
[Phenyl] -3,3-dimethylurea 1.8 g of 1- (3-hydroxyphenyl) -3,3-dimethylurea was dissolved in 20 ml of dry N, N-dimethylformamide, and 0.4 g of 60% sodium hydride was added. After stirring for 15 minutes, 3-[(3,4-dihydro-2,2-dimethyl-2H-
3.6 g of 1-benzopyran-6-yl] ethyl p-toluenesulfonate was added dropwise.

After stirring at room temperature for 5 hours, the mixture was poured into ice water and extracted with ethyl acetate. The organic layer was washed with water and dried over anhydrous sodium sulfate. Ethyl acetate was distilled off under reduced pressure, and the residue was purified by silica gel column chromatography (eluent: n-hexane / ethyl acetate = 1/1) to give 2.4 g of the compound (No. 37) shown in Table 2. Obtained.

In the same manner as in Examples 1 to 4, the compounds shown in Tables 1 to 6 were produced.

 Tables 1 to 6 also show the physical properties of each compound.

Next, preparation examples of the compound of the present invention will be shown. In the following, "parts" and "%" mean "parts by weight" and "% by weight", respectively.

Formulation Example 1 wettable powder 40 parts of the compound of the present invention shown in Tables 1 to 6, Carplex # 80 (Shionogi Pharmaceutical Co., trade name) 20 parts, N, N kaolin clay (Tsuchiya Kaolin Co., trade name) 35 parts , Higher alcohol sulfate ester surfactant Solpol 8070 (Toho Chemical Co.,
(Trade name) 5 parts are blended and uniformly mixed and pulverized to obtain an active ingredient.
A wettable powder containing 40% was obtained.

Formulation Example 2: Granules 1 part of the compound of the present invention shown in Tables 1 to 6, 43 parts of clay (manufactured by Nippon Talc), 55 parts of bentonite (manufactured by Toyoko Yoko Co., Ltd.),
After mixing 1 part of succinate surfactant Eyallol CT-1 (trade name of Toho Chemical Co., Ltd.), mixing and pulverizing,
And kneaded. Further, this is extruded from a hole having a diameter of 0.6 mm using an extrusion granulator, dried at 60 ° C. for 2 hours, and then cut into a length of 1 to 2 mm to obtain a granule containing 1% of an active ingredient. Was.

Formulation Example 3: Emulsion 30 parts of the compound of the present invention shown in Tables 1 to 6 are dissolved in a mixed solvent consisting of 30 parts of xylene and 25 parts of dimethylformamide, and a polyoxyethylene-based surfactant Solpol 3005X (Toho Chemical Co., Ltd. An emulsion containing 30% of the active ingredient was obtained by adding 15 parts of trade name.

Formulation Example 4: Flowable agent 8 parts of ethylene glycol, 30 parts of the compound of the present invention shown in Tables 1 to 6, and Solpol AC3032 previously mixed
(Toho Chemical Co., trade name) 5 parts, xanthan gum 0.1 part,
The mixture was well mixed and dispersed in 56.9 parts of water. Next, this slurry-like mixture is subjected to Dynomill (Shinmaru Enterprises)
To obtain a stable flowable agent containing 30% of the active ingredient.

 Next, test examples of the compound of the present invention will be described.

Test Example 1 Flooded Soil Treatment Test A 1 / 2,500 ares resin vat was filled with alluvial clay loam, and after fertilization, an appropriate amount of water was added to scratch. From the soil surface, the seedlings of the foxtail, kikasigusa and konagi are collected from the soil surface.
Mixed into 5 cm layer.

On the other hand, two paddy rice seedlings (variety: Akinishiki, seedling quality: good) at the second and third leaf stages were planted shallowly at a rate of 3 cm per bat / two strains and an insertion depth of about 1 cm. Thereafter, a water depth of about 3.5 cm was maintained, and a granule containing the compound of the present invention obtained in Preparation Example 2 as an active ingredient on day 3 after transplantation and a comparative compound 1-4 [obtained in the same manner as in Preparation Example 2 Granules containing 2- (4-methylphenyl) ethyloxy] phenyl-3-methoxy-3-methylurea as an active ingredient are dropped on a water-impregnated surface in a predetermined amount so that the amount of the active ingredient is 10 or 5 g / a. Was done. Two days after the treatment, the water depth was reduced to 3 cm / day, and then cultivation was controlled in a greenhouse. On the 21st day after the chemical treatment, the herbicidal effect and the phytotoxicity were investigated.

Table 7 shows the results. In addition, the evaluation of the weeding effect Was calculated and expressed as a herbicidal effect coefficient according to the following criteria.

In addition, the evaluation of phytotoxicity Was calculated and expressed as a phytotoxicity coefficient according to the following criteria.

Test Example 2 Foliage treatment test A small polyethylene pot of 1 / 8,850 are filled with black soil of upland field, fertilized, and seeded with various seeds of Apod, Shiroza, Ichibi, Hokenosa, Yaegura, corn, and barley. Was.

Cultivation management was continued in the greenhouse, and the growth of the test plants was in the two-leaf stage of A. terrestris, the three-leaf stage of Shiroza, the two-leaf stage of Ichibai, the two-leaf stage of Hokuhenosa, the 1.5-leaf stage of corn, the three-leaf stage of corn, and the two-leaf barley stage. Upon reaching, a wettable powder comprising the compound of the present invention obtained in Formulation Example 1 as an active ingredient and a comparative compound 1-4- [2- (4-methylphenyl) ethyloxy] phenyl obtained in the same manner as in Formulation Example 1 A wettable powder containing -3-methoxy-3-methylurea as an active ingredient is diluted with water so that the active ingredient becomes a predetermined amount, and a spray amount per 1 are
An amount equivalent to 10 liters was sprayed with a small power pressurized sprayer. Thereafter, the observation was continued in a greenhouse, and on the 15th day after the application of the chemical, the herbicidal effect and the chemical damage were investigated. Table 8 shows the results. or,
The evaluation of the herbicidal effect and the phytotoxicity was performed in the same manner as in the criteria of Test Example 1.

Claims (2)

(57) [Claims] 1. A compound represented by the following general formula (I) (In the above formula, A represents an alkylene group, and R ¹ , R ² , R ³ and
R ⁴ each independently represents a hydrogen atom or a methyl group,
R ⁵ represents a methyl group or a methoxy group. An N'-phenyl-N-methylurea derivative represented by the formula: 2. The following general formula (I) (In the above formula, A represents an alkylene group, and R ¹ , R ² , R ³ and
R ⁴ each independently represents a hydrogen atom or a methyl group,
R ⁵ represents a methyl group or a methoxy group. A herbicide comprising an N'-phenyl-N-methylurea derivative represented by the following formula as an active ingredient.