JPS6299369A - Isoxazole derivative and insecticidal and miticidal agent - Google Patents

Abstract

NEW MATERIAL:The compound of formula I [R<1> is lower alkyl; R<2> is alkyl or phenyl; R<3> is H or group of formula II (R<4> is lower alkyl; X and Y are O or S)]. EXAMPLE:3-Hydroxy-5-methyl-4-butylthioisoxazole. USE:Insecticidal and miticidal agent. PREPARATION:A compound of formula I wherein R<3> is H can be produced by reacting the compound of formula III (R<5> is lower alkyl having a carbon number of less than R<1> by one; R<6> is 1-4C alkyl) in an inert solvent (preferably a mixture of an alcohol and water) in the presence of a base (preferably an alkali metal hydroxide) at -30-0 deg.C for 10min-5hr, adding an acid (preferably hydrochloric acid, sulfuric acid or nitric acid) to the reaction mixture at a stroke and heating the mixture at 50-150 deg.C. The product can be converted to another compound of formula I wherein R<3> is group of formula II by reacting with diethyl chlorothiophosphate, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a compound represented by the following general formula (1) and an insecticide and acaricide containing the compound as an active ingredient.

(In the formula, R1 represents a lower alkyl group. R2 represents an alkyl group or a phenyl group. R3 represents a water alkyl group,
X and Y are the same or different and represent a sulfur atom or an oxygen atom. ).

As a result of various studies regarding the introduction of a sulfur atom into the 4-position of the inoxazole ring, the present inventors discovered that the method of introducing a sulfur atom into the 4-position of the inoxazole ring was as follows: , a compound represented by the following formula (Step a) is obtained, a compound represented by the formula (from) is obtained by phosphoric acid esterification of the hydroxyl group of the formula (Ia), and a compound represented by the formula (6) is obtained. It was discovered that the compound (It+) has insecticidal and acaricidal activity.

SR2 In each of the above formulas, R5 and R6 represent a lower alkyl group, R7 represents a hydrogen atom, and R8 represents a group 11
shows. R1, R2, R4, X and -p(YR4)
2 Y has the same meaning as above.

In the above formula, R1 &) preferably represents a C1-4 lower alkyl group such as methyl, ethyl, propyl, inclovir, butyl, isobutyl, filter-butyl, t-butyl,
Most preferred is methyl.

When R2 is an alkyl group, for example, methyl,
Preferably C
1-18 alkyl, more preferably C1-8
is an alkyl.

When R5 is a group U or preferably -P(Y
R4)2 is a sulfur atom, Y is preferably an oxygen atom,
and R4 is preferably C1-4 as exemplified for R1
It is an alkyl.

R5 is lower alkyl having one carbon atom less than RI.

R6 is preferably C1-4 alkyl as exemplified for R1.

The compound of formula (Ia) of the present invention is a compound of formula (If
) is obtained according to the following reaction formula by reacting the compound with hydroxylamine.

SR2 Step 1 is preferably carried out in an inert solvent in the presence of a base.

Examples of inert solvents used include alcohols such as methanol, ethanol, impropanol, n-butanol, and t-butanol; ethers such as ether, tetrahydrofuran, dioxane, and dimethoxyethane; and acetonitrile. Nitriles: Amides such as dimethylformamide, dimethylacetamide, hexamethylphosphoryltriamide, or sulfoxides such as dimethyl sulfoxide, or their combinations (includes a mixed bath agent of residual solvent and water, preferably alcohols) It is a mixed solvent with water.

Bases used include, for example, alkali metal alkoxides such as sodium methoxide, sodium ethoxide, potassium t-butoxide, sodium t-bentoxide; sodium hydroxide, potassium hydroxide, calcium hydroxide, barium hydroxide; alkali metal or alkaline earth metal hydroterites; alkaline earth carbonates such as sodium carbonate and potassium carbonate; alkali metal acetates such as sodium acetate and potassium acetate; preferably alkaline It is a metal hydroxide.

Preferably, about 1 equivalent of the above base is used. Further, hydroxylamine is usually used in an amount of 1 to 10 equivalents, preferably 2 equivalents.
It is preferable to use 5 to 5 equivalents. Hydroxylamine is usually used in the form of hydrochloride, sulfate or hydrate.

The reaction temperature is preferably low, usually -78°C
-10°C, preferably 0°C - 0°C, and the time required for one reaction varies depending on the reaction temperature, solvent, etc., but is usually 10 minutes to 5 hours.

Step 2 involves the reaction intermediate hydroxamic acid visiting conductor (2
) is carried out by adding the acid all at once to the reaction mixture obtained in step 1 and immediately heating it.

Inorganic acids such as hydrochloric acid, sulfuric acid, nitric acid, phosphoric acid, or acetic acid, dichloroacetic acid, trichloroacetic acid,
Examples include organic acids such as trifluoroacetic acid, methanesulfonic acid, benzenesulfonic acid, and p-)luenesulfonic acid, preferably hydrochloric acid, sulfuric acid, and nitric acid.

In addition, the above-mentioned acids are used in amounts of 1 or more, preferably 5 to 1.
5 equivalents are used.

The reaction temperature is 30°C to 200°C, preferably 50°C.
C to 150 C, and the time required for the reaction varies depending on the reaction substrate, reaction temperature, etc., but is usually 30 minutes to 4 hours.

After completion of the reaction, the target compound (Ia) is collected from the reaction mixture according to a conventional method. For example, by concentrating one reaction mixture or by pouring it into a large amount of water to collect the precipitated target compound (Ia), 4111. Alternatively, if no precipitation occurs, the target compound can be obtained by extraction with a water-immiscible solvent and distilling off the solvent.

Furthermore, if necessary, the stone can be purified by conventional methods such as recrystallization, column chromatography, etc.

Under the conditions of this reaction, the target compound, 3-hydroxyisoxazole derivative (Ia), is obtained as the main product, but a small amount of 5-hydroxy derivative (■) is also obtained as a by-product of the reaction during the reaction night. Admitted.

When R2 is an alkyl group, the 5-hydroxy compound (IV) is unstable and cannot be stably extracted from a single reaction solution. When R2 is a phenyl group, the 3-hydroxy form (, I
The 5-hydroxy form (IV) can be stably extracted together with a). Furthermore, as shown in the reference example, when R2 is a 2,4-dichlorophenyl group,
The target product CI&) was not obtained, and only the 5-hydroxy form (IV) was obtained.

The compound of formula L Ia) obtained by this reaction has fungicidal activity itself and is therefore useful as an A horticultural boxcide. For example, by pre-pouring the soil, the Pythium fungus, which is the cause of seedling blight of Japanese cucumbers, can be effectively suppressed. In terms of bactericidal activity, R2 is preferably isopropyl or n-butyl. Furthermore, compound (n) is useful as an intermediate for the synthesis of agricultural chemicals.For example, as shown in the missing 3-position, the phosphate ester visiting conductor (To) of the hydroxyl group at the 3-position has insecticidal activity, and is used for improved horticulture. Useful as an insecticide and acaricide.

Compounds of formula (from) are obtained by reacting compounds of (Ia) with di(lower alkyl)thiophosphates, such as diethylchlorothiophosphate.

The reaction is preferably carried out in an inert solvent in the presence of an acid acceptor. In other words, this reaction is.

The reactant is dissolved in an organic solvent such as benzene, toluene, xylene, methylene chloride, dichloroethane, or a solvent inert to the reaction such as acetone, methyl ethyl ketone, acetonitrile, etc., and the acid acceptor is added, and the mixture is heated at room temperature or from 30 to 30 minutes.
This is carried out by heating and stirring at 80°C. At this time, the reaction temperature and the order in which the reactants are added are not particularly limited. Inorganic or organic bases are used as acid acceptors. Examples of inorganic bases that can be used include sodium carbonate, potassium carbonate, sodium hydroxide, potassium hydroxide, and potassium fluoride.

Examples of organic bases include triethylamine, dimethylaniline, and dimethylaminopyridine.

Lutidine, 1,4-diazabicycloCZ & Rioctane (
DABOO) etc. are used.

After the reaction is completed, the reaction product can be collected from the reaction mixture by a conventional method. For example, if the reaction is carried out in a water-soluble solvent such as acetone, the solvent is distilled off after the reaction is completed, and the residue is mixed with water and a water-insoluble solvent such as benzene, ether, methylene chloride, etc. After separating the layers.

The desired product can be collected by washing the organic layer with an aqueous alkali solution and then with water, drying, and then distilling off the solvent. If necessary, impurities can be separated and further purified by conventional methods such as column chromatography.

The compound of formula (Ib) has excellent acaricidal activity against two-spotted spider mites (Tetranychus), apple spider mites, orange spider mites (panon 70hu), rust mites, etc. that parasitize fruit trees, vegetables, and red flowers.It also has excellent acaricidal activity against aphids, black leafhoppers, etc. It is active against various agricultural and horticultural pests such as the brown planthopper and the brown planthopper.It is also active against soil nematodes such as the black nematode.

In order to use the compound of formula (lb) for the above-mentioned purposes, it may be mixed with a carrier and, if necessary, other adjuvants, in the form of a formulation commonly used as an agricultural chemical, such as a powder, coarse powder, fine granule, or fine granule. used in compositions such as wettable powders, emulsions, etc.
Ru. The term "carrier" as used herein refers to a substance that helps the active ingredient compound to reach the site to be treated, and also serves as a storage for the active ingredient compound.

Refers to synthetic or natural inorganic or organic substances that are mixed into a pesticide to facilitate transportation or handling.

The composition of the present invention preferably contains other insecticides to broaden the spectrum.

In some cases, synergistic effects can be expected, and they can be used in combination with fungicides.

Next, the present invention will be explained in more detail by giving synthesis examples, reference examples, formulation examples, and test examples.

Synthesis example 1゜Potassium hydroxide 0.53 ? was dissolved in a mixture of water (5d) and methanol (15d), cooled to -10°C, and α-
Butylthioacetoacetic acid ethyl ester 2061 was added. In addition to this, separately add 2.63 1 hydroxylamine salt
An aqueous solution of t neutralized with a commercial amount of potassium hydroxide (1
0yd) was slowly added dropwise. After reacting at the same temperature for 2 hours, 1128 d of crushed salt was added at once, and immediately heated at 80° C. for 1 hour. The reaction solution was poured into water and extracted with diethyl ether. Wash the extract with water, dry with anhydrous magnesium sulfate,
After concentration, the residue was purified by column chromatography to obtain the desired product of formula (Ia) 1. Oy (Yield: 68 cm)
was obtained as an oil.

IRQfllm:3200~2400,2970.29
50fLX 日日'("l/!" NMR(C!DO15) δIP: 0.91 (t
, 3I (,, r=6.5Hz) 1.2-1.7 (m
, 4H), 2.38 (B, 3H), 167 (
t, 2H.

J=6.5Hz), 11.4 (8, IH,) elemental analysis value (as O[1H15NO2S) analysis value Chi 051.
17 H7, 11N? , 12817.18 Theoretical value% 0
51.31 H7,00N7.48817.12 The same operation as in Synthesis Example 1 was performed to obtain the compounds of Examples 2 to 8.

Synthesis Example 3-Hydroxy-5-methyl-4-phenylthioisoxazole Potassium hydroxide Q, 74f, α-pheny/l/? From oacetoacetic acid ethyl ester LOr and human xylamine salt 15F, the desired product of formula 5 (Ia) 0.783f (yield 30%) was obtained as crystals by the same operation as in Example 1. Furthermore, column chromatography is used to obtain a fraction with a higher polarity ratio. The by-product 5-hydroxy-3-methyl-4-phenylthioisoxazole of formula 1 (ff) was obtained as crystals at 0.31 F (yield: 11.9%).

3-hydroxy form (Ia): melting point 113-114°C.

Engineering Rνnuj0": 3400~2400.1610
crn-1ax NMR (CDC15) δP: 2.40 (B, 31), 7
．． 32 (8°5H), 9.80 (8, IH) Elemental analysis value (as CI 0H9NO2B) Analysis value chi
C, 57, 87H, 4, 58N, 6.78 theoretical value chi
0.5″7.115)(,4,38N,6.78
5-hydroxy form (■): Melting point 142-144℃nuj
ol.

IRν, 2880.1670 cm'ax NMR (CDC14) δP: 2.17 (S, 3H
), 6.8-7.5 (m, 5H), 8.77 (
br, s, IH) Elemental analysis value (CI QH9N○2S
] Analysis value% C, 57, 98H, 4, 3B, N
, 8.87 S, 15.50 theoretical value% c, 57
．． 95 H, 4, 38 N, 6.76 B, 15.4
6 Synthesis Example 10゜Tylthio-3-ynoxasilyl) phosphorothioate Preparation of 0.48 F of 3-hydroxy-5-methyl-4-methylthioinoxazole obtained by the method of Example 2 and 0.48 F of potassium carbonate. 0.632 of diethyl chlorothiophosphate was added to the acetone solution, and the mixture was stirred at room temperature overnight. After the reaction is complete.

The reaction solution was filtered, and the solution was poured into water and extracted with ether. After drying and concentrating the extract over anhydrous sodium sulfate, the residue was subjected to column chromatography to obtain 0.422% (yield: 44.5%) of the desired product of Formula 1 (Ib) as an oil.

fll's -1 1Rν: 15B5cm IDl, 5009a
x NMR (CDC15) δ:t4z(t, θH,, r=I
Hz) 128 C, S, 3K), 2.44 (El,
3H), 4.27((L, 2H.

J=7 Hz) + 4-44 <, q, 2 H,
:J = 7 HZ) Elemental analysis value (C9H16NO4P
As S2) Analysis value% 036.80 N5.60 N
4.72 Flo, 95820.78 Barber straight C36, 36N5.42 N4.71 P
lo, 42821, 57 The same operation as in Synthesis Example 10 was performed to obtain the compounds of Examples 11 to 18.

Reference Example 1 From 0.73 f of aqueous potassium, 42 α-(2,4-dichlorophenylthio)acetoacetic acid ethyl ester, and 3.61 hydroxylamine hydrochloride! 3. By the same operation as A jelly 9. Of (yield: 83°) was obtained as crystals.

Melting point: 136-139C.

ntLjol −+ 工Ry
:300G ~2200.1680cr! Lax NMR (CDC15) δIF; 120 (8,3H), 6
．． 8(br, s.

I H), 6.75-7.5 (m, 3H) elemental analysis (C
As IQH7NO2012s) Analysis value% 0.43.
42 H, 2,83 N, 4.69 S, 1181 theoretical value% C, 43,50 H, 2,56 N, 5.07
S, 11.81 5 parts of Compound No. 11, 50 parts of Merck, and 45 parts of kaolin were uniformly mixed to obtain a powder.

50 parts of Compound No. 14, 20 parts of clay, 10 parts of silica frozen earth, 5 parts of white carbon, 3 parts of sodium lignin sulfonate, 2 parts of Nucol+106 (Nippon Nyukazai company regulations product name) and 1 part of polyvinyl alcohol in a mixing machine. The mixture was mixed uniformly using a hammer mill and ground three times using a hammer mill to obtain a wettable powder.

70 parts of Compound No. 13 was finely ground, and 30 parts of clay was added thereto and mixed in a mixer to obtain a premix. 10 parts of this premix were homogeneously mixed in a mixer with 80 parts of clay and 30 parts of bentonite. Add an appropriate amount of water to this mixture, knead it in a kneader,
Extruded through a screen with a diameter of 0.8 tran, 50
Dry in a ventilated dryer at °C. This product was sized using a sifter to obtain granules.

Insect test One cabbage leaf piece was treated with the compound of the present invention at 100F or 20F.
It was immersed in a chemical solution containing 1% m for 30 seconds, and after air drying, it had a diameter of 8.
01! The container was transferred to a plastic container, and 10 3rd instar Spodoptera larvae were placed thereon, and the number of live and dead bundles was determined 72 hours later. We inoculated 10 animals in two rows per district, and examined the mortality rate 72 hours later.

Table 1 Cabbage leaf pieces were treated with 500Pt or 100Pt of the compound of the present invention.
In a chemical solution containing P [soaked for 30 seconds, after air drying, diameter 8C]
Placed in an IFL plastic ice cream cup,
The entangled larvae of the diamondback moth were sprayed into it with a sprayer. This leaf was passed through the petiole and divided into two rows in one section, and the results are shown in Table 2.

Table 2 Remove leaves from Komatsuna seedlings infested with green peach aphid, apply 10 d of 100 P chemical solution per leaf, and add water.
The mice were inserted into a 3 Q rttl bottle, the mouth of the bottle was closed with absorbent cotton, and the mortality rate was examined after 72 hours at 25°C. The results are shown in Table 3.

A hydrating powder was prepared according to the method of Example 2 of 3rd surface-splitting agent, diluted with water to a predetermined amount, and 0.01% of a spreading agent was added thereto to prepare a chemical solution. Cowpea leaves infested with adult two-spotted spider mites were immersed in this chemical solution for 10 seconds, air-dried, and left in a thermostatic chamber at 25°C for 1 hour.
The acaricidal effect after 2 hours was judged according to the following efficacy evaluation criteria table. The average number of adult spider mites tested was 50 in each treatment area. The results are shown in table f1!4.

Efficacy Evaluation Criteria Table 4 Test Example A predetermined amount of 2% powder of the test compound was sprayed in a plastic cylinder to pots in which black leafhopper and brown planthopper were planted. Ten to 15 entangled larvae of both the resistant leafhopper and brown planthopper species were released into the cylinder, and the mortality rate after 72 hours was calculated from the sum of the two pots. The results are shown in Table 5.

Table 5 %ken applicant Sankyo Co., Ltd.

Claims (2)

[Claims] (1) Compounds represented by the following general formula: ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R^1 represents a lower alkyl group. R^2 represents an alkyl group or a phenyl group. R^ 3 indicates a hydrogen atom or group ▲There are mathematical formulas, chemical formulas, tables, etc.▼, and R^4
represents a lower alkyl group, and X and Y are the same or different and represent a sulfur atom or an oxygen atom. ). (2) Insecticide and acaricide whose active ingredient is a compound represented by the following general formula: ▲There are mathematical formulas, chemical formulas, tables, etc.▼ (In the formula, R^1 represents a lower alkyl group. R^2 represents an alkyl group. group or phenyl group.R^3 indicates a hydrogen atom or a group ▲There are mathematical formulas, chemical formulas, tables, etc.▼, and R^4
represents a lower alkyl group, and X and Y are the same or different and represent a sulfur atom or an oxygen atom. ).