JPH0820583A - Triazole derivative, herbicidal composition for paddy field and its usage - Google Patents

Abstract

PURPOSE:To obtain the subject compound useful as a herbicide in a paddy field, capable of manifesting excellent controlling effects on important weeds in a paddy field in a small dose, nontoxic to rice plants and having selectivity for crops. CONSTITUTION:This 1,2,4-triazole derivative of formula I (R1 and R2 are each H or a lower alkyl; R3 is a lower alkyl; X is O or S). The compound of formula I is obtained by reacting, e.g. (thio)carbazides of formula II with trifluoroacetic anhydride. Furthermore, the (thio)carbazides of formula II and the trifluoroacetic anhydride are used in the following amounts: the latter in a molar amount of preferably about 1.2-1.5 times based on the former. Furthermore, this herbicide for a paddy field is preferably prepared so as to contain about 0.5-90wt.% compound of formula I.

Description

Detailed Description of the Invention

[0001]

The present invention relates to a triazole derivative,
The present invention relates to a paddy herbicide composition and a method for using the same.

[0002]

2. Description of the Related Art To date, many herbicides have been found,
Some of them have been developed as herbicides for paddy fields. However, a drug that has no phytotoxicity to rice and is effective in various paddy important weeds at a low dose has not yet been found.

US Pat. No. 5,108,486 discloses that
It has been disclosed that certain 4-phenyl-1,2,4-triazole derivatives have herbicidal activity. However, in the above specification, although test examples under field conditions are described, they do not necessarily show sufficient herbicidal activity, and the herbicidal effect on paddy weeds under flooded conditions and under the same conditions There is no data showing crop selectivity for rice.

[0004]

DISCLOSURE OF THE INVENTION The inventors of the present invention have taken the above background into consideration.
I have been interested in -phenyl-1,2,4-triazole derivatives and have been conducting detailed studies on the herbicidal effects of these derivatives on paddy field weeds in flooded soil treatment and on crop selectivity for rice. As a result, US Pat.
The 1,2,4-triazole derivative represented by the following general formula (I), which is neither disclosed nor suggested in the specification of No. 6, has no phytotoxicity on rice in a flooded soil treatment test, and has a low dose, which is important for paddy fields. It has been found to have a very high selectivity for the complete eradication of weeds. The present invention has been completed based on these findings.

That is, the present invention has the general formula

[0006]

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[In the formula, R ₁ and R ₂ are the same or different and each represents a hydrogen atom or a lower alkyl group. R ₃ represents a lower alkyl group. X represents an oxygen atom or a sulfur atom. ] The 1,2,4-triazole derivative represented by these, the paddy field herbicide composition which uses this derivative as an active ingredient, and the usage method of the paddy field herbicide composition used in the flooded soil treatment method of a paddy field.

In the above general formula (I), examples of the lower alkyl group include methyl, ethyl, n-propyl, isopropyl, n-butyl and tert-butyl groups.

The compounds of the present invention represented by the above general formula (I) include the following compounds.

Compounds of the general formula (I) in which R ₁ and R ₂ are hydrogen atoms and R ₃ is a methyl group; Compounds of the general formula (I) in which R ₁ and R ₂ are hydrogen atoms and R ₃ is an ethyl group ; R ₁
Is a hydrogen atom, R ₂ and R ₃ are methyl groups; a compound of the general formula (I); R ₁ is a hydrogen atom, R ₂ is a methyl group, R
Compounds of general formula (I) in which ₃ is an ethyl group; R ₁ and R
A compound of the general formula (I) in which ₃ is a methyl group and R ₂ is a hydrogen atom; a compound of the general formula (I) in which R ₁ is a methyl group, R ₂ is a hydrogen atom and R ₃ is an ethyl group; R ₁ , A compound of the general formula (I) in which R ₂ and R ₃ are methyl groups; a compound of the general formula (I) in which R ₁ and R ₂ are methyl groups and R ₃ is an ethyl group.

The compound represented by the general formula (I) of the present invention is produced, for example, by the method shown in the following reaction formula-1.

[0012]

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[In the formula, R ₁ , R ₂ , R ₃ and X are the same as defined above. According to the above Reaction Scheme-1, the compound of the present invention has the general formula (I
It is produced by reacting the (thio) carbazide represented by I) with trifluoroacetic anhydride. Examples of the solvent used in this reaction include aromatic hydrocarbons such as benzene and toluene, halogenated hydrocarbons such as dichloromethane, 1,2-dichloroethane and chloroform, and mixed solvents thereof. General formula (I
The use ratio of (thio) carbazide of I) and trifluoroacetic anhydride is not particularly limited, but
Usually, the latter is used in an amount of about 0.5 to 2 times, preferably about 1.2 to 1.5 times the molar amount of the former. The above reaction proceeds well in the temperature range from room temperature to the boiling point of the solvent used, and the reaction is usually completed in about 1 to 5 hours.
In the above Reaction Scheme-1, the (thio) carbazides of the general formula (II) used as a starting material are prepared by known methods [S
synthesis-Stuttgart, (12), 9
23 (1989)].

The compound of the present invention is completely harmless to rice,
Since it is possible to selectively control grasses and broad-leaved weeds, such as the genus Ceratophyta and the genus Novier other than the same genus Gramineae, it is extremely effective for improving the production of paddy rice and controlling harmful weeds in paddy fields.

When the compound of the present invention is used as a herbicide for paddy fields, emulsions, wettable powders, water solutions, granules, fine granules, granules, powders, spray preparations, aerosol preparations, microcapsule preparations, fumigation preparations. It can be used in various preparation forms such as preparations and smoke preparations.

As the auxiliary agent to be added to the paddy field herbicide of the present invention, those generally used in this field can be widely used, for example, diatomaceous earth, kaolin, clay, bentonite, white carbon, talc and the like extenders. Nonionic surfactants such as polyoxyethylene alkyl ether, polyoxyethylene alkyl ester, polyoxyethylene sorbitan alkyl ester, alkylbenzene sulfonate, alkyl sulfosuccinate, alkyl sulfate, polyoxyethylene alkyl sulfate,
Examples thereof include anionic surfactants such as alkyl sulfonates, allyl sulfonates, and lignin sulfites.

Various organic solvents, various aerosol propellants, various natural minerals, various synthetic compounds and the like can be used as the solubilizers and diluents to be added to the paddy field herbicide of the present invention. For example, as the organic solvent, benzene, toluene, xylene, ethylbenzene, chlorobenzene, alkylnaphthalene, chloroethylene, cyclohexanone,
Methyl ethyl ketone, methyl isobutyl ketone, alcohols, cellosolves, dimethylformamide, dimethylsulfoxide, acetonitrile, mineral oil fractions and water are preferably used. Examples of aerosol propellants include propane, butane, halogenated hydrocarbons, nitrogen, carbon dioxide and the like.

Furthermore, the herbicide for paddy field of the present invention may be colored with an organic or inorganic dye.

In the present invention, in producing the above-mentioned various preparations, the compound of the present invention may be contained in an amount of about 0.1 to 95% by weight, preferably about 0.5 to 90% by weight. Good. The thus-obtained preparation may be used as it is or diluted with a carrier or water, but may be freely added in a range of about 0.0001 to 100% by weight, preferably about 0.001 to 10% by weight depending on the purpose. It is recommended to dilute it before use.

Although the use of the herbicide for paddy field of the present invention is not particularly limited, it is preferable to use the herbicide of the present invention in the method for treating flooded soil in paddy field. As an example of its use, for example, 4 to 6 days after rice planting, the composition of the present invention (granule) may be sprayed on paddy fields kept in a flooded state to control weeds in paddy fields.

[0021]

EXAMPLES The present invention will be further clarified with reference to production examples, formulation examples and test examples below. In the formulation examples, “parts” means “parts by weight”.

Production Example 1 A compound of the general formula (I) wherein R ₁ is a methyl group, R ₂ is a hydrogen atom, R ₃ is a methyl group and X is a sulfur atom (Compound 1).
Preparation of thiosemicarbazito 5.3 mmol toluene 30 ml
To the suspension, 6.9 mmol of trifluoroacetic anhydride was added dropwise under ice cooling, and after completion of the addition, the reaction mixture was stirred at room temperature for another 3 hours. The reaction solution was washed with 10% aqueous sodium carbonate solution and dried over anhydrous magnesium sulfate. The solvent is distilled off, and the residue is a silica gel column (developing solvent; hexane:
The product was purified with ethyl acetate = 4: 1) to obtain 2.0 g of the desired product as white crystals (Compound 1).

Melting point 113-114 ° C. ¹ H-NMR (CDCl ₃ ) δ ppm; 2.56 (3
_{H, CH 3 -C), 3.92} (3H, CH 3 -N),
6.63 (1H, CH = C), 7.22 (1H, aromatic H).

The following compounds were obtained in the same manner as in Production Example 1 above using appropriate starting materials.

Compound of general formula (I) wherein R ₁ is a methyl group, R ₂ is a methyl group, R ₃ is a methyl group and X is a sulfur atom (Compound 2); melting point 104-105 ° C. ¹ H-NMR (CDCl ₃ ) δppm; 2.35, 2.
_{42 (6H, CH 3 -C)} , 3.89 (3H, CH 3 -
N), 7.22 (1H, aromatic H).

Compound of the general formula (I) in which R ₁ is a methyl group, R ₂ is a methyl group, R ₃ is a methyl group and X is an oxygen atom (Compound 3); melting point 109-110 ° C. ¹ H-NMR (CDCl ₃ ) δppm; 2.35, 2.
_{42 (6H, CH 3 -C)} , 3.62 (3H, CH 3 -
N), 7.24 (1H, aromatic H).

Compound of the general formula (I) in which R ₁ is a methyl group, R ₂ is a hydrogen atom, R ₃ is a methyl group and X is an oxygen atom (Compound 4); melting point 115-116 ° C. ¹ H-NMR (CDCl ₃ ) δppm; 2.56 (3
_{H, CH 3 -C), 3.63} (3H, CH 3 -N),
6.60 (1H, CH = C), 7.24 (1H, aromatic H).

Compounds of the general formula (I) in which R ₁ is a hydrogen atom, R ₂ is a methyl group, R ₃ is a methyl group and X is a sulfur atom (Compound 5); melting point 111-112 ° C. ¹ H-NMR (CDCl ₃ ) δppm; 2.52 (3
_{H, CH 3 -C), 3.90} (3H, CH 3 -N),
7.24 (1H, aromatic H), 7.40 (1H, CH =
C).

Compound of the general formula (I) wherein R ₁ is a hydrogen atom, R ₂ is a methyl group, R ₃ is a methyl group and X is an oxygen atom (compound 6); melting point 114-115 ° C. ¹ H-NMR (CDCl ₃ ) δppm; 2.52 (3
_{H, CH 3 -C), 3.90} (3H, CH 3 -N),
7.24 (1H, aromatic H), 7.40 (1H, CH =
C).

Compound of the general formula (I) wherein R ₁ is a hydrogen atom, R ₂ is a hydrogen atom, R ₃ is an ethyl group and X is a sulfur atom (Compound 7); melting point 113-114 ° C. ¹ H-NMR (CDCl ₃ ) δppm; 1.30 (3
_{H, CH 3 -C), 3.86} (2H, CH 2 -N),
6.30 (1H, CH = C), 7.24 (1H, aromatic H), 7.40 (1H, CH = C).

Compound of the general formula (I) wherein R ₁ is a hydrogen atom, R ₂ is a hydrogen atom, R ₃ is a methyl group and X is an oxygen atom (Compound 8); melting point 127-128 ° C. ¹ H-NMR (CDCl ₃ ) δppm; 3.60 (3
_{H, CH 3 -N), 6.30} (1H, CH = C), 7.
24 (1H, aromatic H), 7.40 (1H, CH =
C).

Formulation Example 1 (10% wettable powder) Compound of the general formula (I) 10.0 parts Dichlorite (Cullion clay: manufactured by Siklite Industry Co., Ltd.) 87.3 parts Solpol 800A 1.35 parts Lunox P-65-L (manufactured by Toho Chemical Industry Co., Ltd.) 1.35 parts Formulation Example 2 (10% granules) Compound of general formula (I) 10.0 parts Sodium lignin sulfonate 0.5 parts Dodecylbenzene sulfonic acid Sodium 2.0 parts Diatomaceous earth 27.5 parts Bentonite 60.0 parts Test Example 1 (flooded soil treatment test) A porcelain pot having an outer diameter of 9.2 cm, an inner diameter of 8.5 cm, and a height of 9.0 cm was previously placed in a mixer. Put cultivated loam soil prepared by adding water to an appropriate viscosity and an appropriate amount of mixed fertilizer, and add Nobie, firefly, broad-leaved weeds (Cyperaceae, Azena) to the soil surface,
Seeds of cypress and eel were sown. After lightly squeezing to flatten the soil surface, 2-leaf stage rice (cultivar: Akinishiki) was transplanted and submerged to a depth of about 3 cm. Three days later,
The test compound was sprayed uniformly on the submerged surface so that the amount of active ingredient was a predetermined ratio. The drug solution for spraying is the above-mentioned Formulation Example 1
The wettable powder having the formulation shown in (1) was diluted with water and uniformly dropped on the submerged surface with a pipette. Three weeks after spraying the chemical solution, the herbicidal effect on rice and various weeds was investigated according to the following criteria, and the results are shown in Table 1. The test compound numbers in Table 1 correspond to the compound numbers in the above Production Examples.

Criteria: 5 ... 100% herbicide (complete death), 4.5 ... 90-100% herbicide, 4 ... 70 herbicide
~ 90%, 3 ... Herbicide rate 40-70%, 2 ... Herbicide rate 20-
40%, 1 ... grazing rate 0-20%, 0 ... grazing rate 0% (harmless).

[0034]

[Table 1]

[0035]

INDUSTRIAL APPLICABILITY According to the present invention, there is provided a herbicide for paddy fields, which exhibits an excellent controlling effect on important weeds in paddy fields in a small amount and is harmless to rice.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Isao Tada 615, Satoura, Satoura-cho, Naruto, Tokushima Prefecture, inside Naruto Laboratory, Otsuka Chemical Co., Ltd. (72) Minoru Motoki 615, Satoura, Satoura, Naruto, Tokushima Prefecture Otsuka (72) Inventor ▲ Yanagi ▼ ▲ Se ▼ Daisuke 615, Satoura-cho, Satoura-cho, Naruto-shi, Tokushima Prefecture Otsuka Chemical Co., Ltd. Naruto Laboratory

Claims (3)

[Claims] 1. A compound of the general formula [In the formula, R ₁ and R ₂ are the same or different and each represents a hydrogen atom or a lower alkyl group. R ₃ represents a lower alkyl group. X
Represents an oxygen atom or a sulfur atom. ], 1, 2,
4-triazole derivative. 2. A herbicide composition for paddy fields, which comprises the 1,2,4-triazole derivative according to claim 1 as an active ingredient. 3. The method for using the herbicide composition for paddy fields according to claim 2, which is used in a method for treating flooded soil in paddy fields.