JPH0543518A - Haloalkyl phenyl ketone derivative and seed disinfection agent - Google Patents

Abstract

PURPOSE:To provide a new haloalkyl phenyl ketone derivative having high safety and remarkably high disinfection activity to the seed affected by blight such as bakanae disease and helminthosporium leaf spot of rice plant, especially bakanae disease. CONSTITUTION:The haloalkyl phenyl ketone derivative of formula I (R1 is H, CH3 or phenyl; R2 is CN or NO2; X1 is H or halogen; X2 is halogen), e.g. 2-bromo-1-(2-methoxy-4-methylphenyl)-2-nitroethanone. The compound can be produced by reacting a new phenyl ketone derivative of formula 2 with a halogenation agent such as chlorine, bromine, iodine, sulfuryl chloride, cupric chloride and tribromopyrrolidone in a solvent. The new substance of formula 2 is easily synthesizable by conventional process.

Description

Detailed Description of the Invention

[0001]

[Object of the Invention]

FIELD OF THE INVENTION The present invention relates to novel haloalkyl phenyl ketone derivatives. More specifically, it relates to a haloalkylphenylketone derivative represented by the following general formula (1) and a seed disinfectant containing the derivative as an active ingredient. Therefore, the present invention is useful in the chemical industry and the fields of agriculture and horticulture, especially in the field of agrochemical manufacturing.

[0002]

2. Description of the Related Art So far, a method for synthesizing .alpha.-chloro-.beta.-oxo-benzenepropanenitrile as a compound similar in chemical structure to the compound of the present invention has been described.
Dura Society Cimic France 1969 p.628). However, the compound represented by the general formula (1) of the present invention is not known.

[0003]

Although various chemicals have been used as seed disinfectants against rice barley seedling disease and the like, they have become unusable or their use has been restricted due to the problem of drug resistance. Therefore, there are some bactericides that are not always satisfactory. Therefore, in these fields, the emergence of a novel fungicide having a skeleton different from that of conventional drugs and having high safety is demanded.

The present invention seeks to provide a novel fungicide that meets these needs.

[0005]

[Constitution of the invention]

[Means for Solving the Problems] In order to achieve the above-mentioned object, the present inventors have synthesized a number of compounds and have made extensive studies on their usefulness. As a result, the haloalkyl phenyl ketone derivative represented by the following general formula (1) is a novel compound that has not been described in the literature, and has a remarkable seed disinfecting activity and safety for disease-infected seeds, especially rice scab-infected paddy rice. I found a thing.

Therefore, the gist of the first aspect of the present invention lies in the following general formula (1):

[0007]

[Chemical 3]

(Wherein R ₁ represents a hydrogen atom, a methyl group or a phenyl group, R ₂ represents a cyano group or a nitro group,
X ₁ represents a hydrogen atom or a halogen atom, and X ₂ represents a halogen atom).

A second aspect of the present invention is a seed disinfectant containing the haloalkylphenylketone derivative represented by the general formula (1) as an active ingredient. Next, Table 1 shows specific examples of the compound of the present invention represented by the general formula (1). Compound No. Is also referred to in the following examples and test examples.

[0010]

[Chemical 4]

[0011]

[Table 1]

[0012]

The compound of the general formula (1) of the present invention is a novel compound. The compound of formula (1) then acts as the active ingredient of the seed disinfectant.

[0013]

【Example】

Method for Producing Compound of the Present Invention The compound of the general formula (1) of the present invention is produced by the method described below. It can be produced by reacting the phenyl ketone derivative represented by the general formula (1) with a suitable halogenating agent in a solvent.

[0014]

[Chemical 5] (In the formula, R ₁ , R ₂ , X ₁ , and X ₂ have the same meanings as described above.)

The halogenating agent used in this reaction includes chlorine, bromine, iodine, sulfuryl chloride, cupric bromide, pyrrolidone tribromide and the like.

As the solvent, halogenated hydrocarbons such as dichloromethane, chloroform and carbon tetrachloride, alcohols such as methanol and ethanol, esters such as ethyl acetate, acetic acid, dioxane and water and mixed solvents thereof can be used. ..

The reaction temperature may be in the range of 0 ° C. to the boiling point of the solvent, but it is usually in the range of 0 ° C. to room temperature.

After completion of the reaction, the compound of the present invention can be obtained by adding water and an organic solvent such as toluene or chloroform to fractionate the desired product and distill off the solvent.

Examples of production by this method are shown in Examples 1 and 2. The compound of formula (2), which is a starting material, is a novel compound, but can be easily synthesized by a known method.

Example 1 Preparation of 2-bromo-1- (2-methoxy-4-methylphenyl) -2-nitroethanone (Compound No. 4) 1- (in a 100 ml four-necked flask equipped with a stirrer. 4.2 g of 2-methoxy-4-methylphenyl) -2-nitroethanone and 60 ml of acetic acid were added, 3.2 g of bromine was added dropwise to this mixture at 10 ° C., and the mixture was stirred at the same temperature for 30 minutes. After the reaction was completed, water was added and the mixture was extracted with chloroform. The organic layer was washed with water and dried over anhydrous sodium sulfate. When the solvent was distilled off under reduced pressure, 2.7 g of the title compound was obtained as brown crude crystals. Recrystallization from a mixed solvent of toluene and n-hexane gives colorless crystals with a melting point of 9
The temperature was 2.5 to 94.5 ° C.

Example 2 2-Bromo-2-phenyl-1
Production of-(2-methoxy-4-methylphenyl) -3-oxopropanenitrile (Compound No. 8) 2-phenyl-1- (2-methoxy-4) was added to a 200 ml four-necked flask equipped with a stirrer. -Methylphenyl) -3-oxopropanenitrile 4 g, acetic acid 60 m
1, 60 ml of chloroform were added, 2.4 g of bromine was added dropwise to this mixture at room temperature, and the mixture was stirred at room temperature for 2 hours. After the reaction was completed, water was added and the mixture was extracted with chloroform. The organic layer was washed with water and dried over anhydrous sodium sulfate. The solvent was distilled off under reduced pressure to obtain 4.8 g of the title compound as brown crude crystals. When recrystallized with a mixed solvent of toluene and n-hexane, colorless crystals are obtained with a melting point of 110-11.
It showed 1 ° C.

Example Method for Formulating a Seed Disinfectant of the Present Invention When used as a seed disinfectant according to the present invention, it is formulated into a generally used form such as a wettable powder, an emulsion, a hydrated granule, and a flowable powder. Can be used. The carrier used may be either solid or liquid and is not limited to a particular carrier. Examples of the solid carrier include various clays, kaolin, clay, diatomaceous earth, talc,
Examples thereof include silica.

As the liquid carrier, those which serve as a solvent for the active ingredient compound of the present invention and nonsolvents can be used so long as they can disperse or dissolve the active ingredient compound with an auxiliary agent. For example, benzene, xylene, toluene, kerosene, alcohols, ketones, dimethylsulfoxide, dimethylformamide and the like can be used. To this, a suitable surfactant and other auxiliary agents such as a spreading agent and a fixing agent are mixed, and a wettable powder,
It can be used as an emulsion, hydrated granule or flowable. The content of the seed disinfectant of the present invention is 10% of the total amount of the preparation.
-15% by weight (wt%) is suitable. In addition, the compound of the present invention can be used as a mixture with other seed disinfectants in order to save labor and ensure control effects.

Next, Examples 3 to 4 will be shown for a method of formulating the compound according to the present invention as a seed disinfectant, but the present invention is not limited to the following Examples.

Example 3 (Wettable powder) Compound No. 1 part 30 parts, white carbon
15 parts, 3 parts of polyoxyethylene alkylaryl ether, 2 parts of sodium lignin sulfonate and 50 parts of clay are mixed and sufficiently ground to give 30% of active ingredient.
A wettable powder containing is obtained.

Example 4 (Emulsion) Compound No. 20 parts of the compound of Example 7, 10 parts of polyoxyethylene nonylphenyl ether and 70 parts of xylene are mixed and dissolved to obtain an emulsion containing 20% of the active ingredient.

The wettable powder and emulsion of Examples 3 to 4 above were mixed with water to form 1 part.
Dilute the seed pad to 0 to 1000 times and soak the seed pad in a liquid of 1 to 2 times the weight of the seed pad for 10 minutes to 48 hours, or, in the case of a wettable powder, add 0.1 to 1.0% by weight of the seed pad. By well dressing the seed paddy, it is possible to control seed-borne diseases such as inoculum seedling disease and rice sesame leaf blight.

[0028]

The action and effect of the compound of the present invention as a seed disinfectant will be described below with reference to test examples.

[0029]

[Test example]

Test Example 1 Test for disinfecting seeds of rice bran seedling disease Seeds of flowering stage using spore suspension of benomyl-resistant strain of rice bran disease and susceptible rice bran plant ( Gibberella fujikuroi ) cultivated in steam-sterilized rice straw medium. The cultivar Nihonbare) was spray-inoculated twice each to obtain rice paddy-rice seedlings-infected paddy rice (two types of paddy rice infected with resistant bacterium and paddy infected with susceptible bacterium).

Rice bran disease infected rice obtained by the above-mentioned method was prepared according to the wettable powder of Example 1 and diluted with a predetermined concentration of each drug to give a seed rice to drug ratio (v / v) of 1: 1. 2 at 20 ° C
It was immersed for 4 hours. Then, germinate at 30 ° C for 24 hours,
The dove chest-shaped rice seeds were sown on Kumiai granular soil (Kureha Chemical Industry Co., Ltd.) according to a conventional box raising method. After that, cultivation was managed in a glass greenhouse.

30 days after sowing, the number of diseased seedlings and the number of healthy seedlings showing stupid seedling disease such as maternity and death were investigated 30 days after sowing (the number of seedlings investigated per ward was about 200). The rate (%) was calculated. From this, as shown by the following equation, the seed disinfection rate (%) was calculated in comparison with the diseased seedling rate in the untreated plot.
Regarding the phytotoxicity, the germination rate, the degree of growth, etc. were observed and the following phytotoxicity index was used.

[0032]

[Equation 1]

[0033]

[Equation 2]

Drug damage index 0 = no drug damage 1 = small 2 = medium 3 = large 4 =
Jin

The results are shown in Table 2.

[0036]

[Table 2]

Note 1) Comparative agent 1

[0038]

[Chemical 6] (Burten de la Societe Simique France 1
969, compound described on page 628) Note 2) Indicates a commercially available fungicide, Benlate (generic name: benomyl). Note 3) The figures in parentheses indicate the diseased seedling rate (%) in untreated plots.

Test Example 2 Rice sesame leaf blight seed disinfection effect test Sesame leaf blight fungus ( Cochliobolus Myochianus Cochliobolu) naturally infected in a field where rice sesame leaf blight frequently occurs
s. miyabeanus ) -infected paddy (variety: Golden Hare) was collected and used as a test paddy.

The seed disinfection method and other operating procedures were the same as those of the test for disinfecting the seeds of the horse mackerel disease in Test Example 1.

For the disease onset, the number of rice sesame leaf blight diseased seedlings was examined 20 days after sowing, and the diseased seedling rate (%) was determined in the same manner as in Test Example 1, and the seed disinfection rate (%) was calculated from this. In addition, the same criteria as in Test Example 1 were investigated for chemical damage.

The results are shown in Table 3.

[0043]

[Table 3]

Note 1) The same compound as Comparative Agent 1 of Test Example 1. Note 2) Lobral (generic name: isoprodione) 3- (3,5-dichlorophenyl) -N-2,4, a commercially available fungicide
-Dioxoimidazolidine-1-carboxamide.

Front page continuation (72) Inventor Kazuo Kajikawa 2385 Toda, Atsugi City, Kanagawa Prefecture

Claims (2)

[Claims] 1. A general formula: (In the formula, R ₁ represents a hydrogen atom, a methyl group or a phenyl group, R ₂ represents a cyano group or a nitro group, X ₁ represents a hydrogen atom or a halogen atom, and X ₂ represents a halogen atom. The haloalkyl phenyl ketone derivative represented by these. 2. A general formula: (In the formula, R ₁ represents a hydrogen atom, a methyl group or a phenyl group, R ₂ represents a cyano group or a nitro group, X ₁ represents a hydrogen atom or a halogen atom, and X ₂ represents a halogen atom. The seed disinfectant characterized by containing the haloalkyl phenyl ketone derivative represented by these as an active ingredient.