JPH0262843A - Production of trans-2,2-dimethyl-3-(2,2-dichlorovinyl)-cyclopropanecarboxylic acid halide - Google Patents

Abstract

PURPOSE:To obtain a trans-form of the title substance under a mild condition by treating a cis-form or a mixture of cis-form/transform phosphorus iodide or silicon iodide in the presence of preferably an iodine halide. CONSTITUTION:1mol cis-form or a cis/trans mixture of a compound shown by the formula (X is halogen) is reacted with 1/100-1/5mol phosphorus iodide or silicon iodide (e. g., phosphorus triiodide or silicon tetraiodide) preferably in a halogenated hydrocarbon solvent at 60-120 deg.C for 30 minutes-20 hours to give a transform. The reaction can be more smoothly advanced by adding 1/100-1/10mol based on 1mol dichloroacid halide of the iodine halide (e. g., bromine iodide or chlorine iodine). The compound shown by the formula is used as an intermediate for an acid component of permethrin and trans-form has lower toxicity to warm-blooded animals.

Description

Detailed Description of the Invention <Industrial Application Field> The present invention relates to cis-2,2-dimethyl-3-(2, 2-dichlorovinyl)-
trans-2,2-dimethyl-3-(2,
The present invention relates to a method for producing 2-dichlorovinyl)-cyclopropanecarboxylic acid halide.

<Conventional technology 0 Problems to be solved by the invention> 2.2-
Dimethyl-3-(2,2-dichlorovinyl)-cyclopropanecarboxylic acid C Hereinafter, it will be abbreviated as dichloroic acid. ) constitutes the acid component of the insecticides vermethrin, cybelmethrin, etc., which have excellent efficacy not only for household and epidemic prevention purposes but also against agricultural pests and forest pests. Dichloroacid halide is useful as an intermediate for these insecticides.

Dichloric acid halide has cis and trans geometric isomers based on a three-membered ring, but esters derived from the trans isomer are less toxic to mixed-breed animals than esters derived from the cis isomer. It has been known. (Na
ture, 244, 456 (1973)).

However, dichloroacid halide is produced as a mixture of trans and cis forms. Therefore, converting the cis form to the trans form has important industrial significance.

Hitherto, a method of heating to 160° C. has been known as a method for converting the cis form of dichloroacid halide into the trans form (Japanese Patent Application Laid-open No. 131953/1983).

However, this method has the problem of requiring high temperatures; for example, at 100°C, trans conversion hardly progresses.

Means for Solving the Problems〉 The present inventors have conducted intensive studies to find a better method for producing the trans isomer by converting the cis isomer of dichloroacid halide. It was discovered that iodides of iodine, etc., were surprisingly advantageous in trans-converting cis isomers even under mild conditions, and that trans-conversion proceeded even more smoothly when carried out in the coexistence of halides of iodine. After further various studies, the present invention was completed.

That is, the present invention involves the action of phosphorus iodide or silicon iodide on cis or cis/trans mixed dichloroacid halide represented by formula (1)-(1) (wherein, X represents a halogen atom). The present invention provides an industrially excellent method for producing trans-dichloroacid halide characterized by (2) and a method for producing (1) which is carried out in the presence of an iodine halide.

Next, the method of the present invention will be explained in detail.

Examples of dichloroyl halide (1) which is a raw material of the present invention include dichloroyl chloride and dichlorobromide, but chloride is usually used industrially from the viewpoint of ease of handling and price.

In addition, dichloroyl halide may be used alone in the cis form or as a mixture with the trans form in any proportion; however, from the perspective of the purpose of the present invention, it is important to use dichloric acid halide in the cis form alone or in the cis form. Needless to say, it will be effective.

Typical examples of the phosphorus iodide and silicon iodide used in the present invention include phosphorus triiodide and silicon tetraiodide, and the amount used is usually 1/1/1 relative to the dichlorohalide to be treated. 200 to 1 mole, preferably 1/100
~115 mole times.

In the present invention, the trans conversion reaction can be made to proceed more smoothly by coexisting an iodine halide, but in this case, the amount used is usually 1/Zoo to 1 mole based on the dichloroacid halide to be treated. , preferably 1/
It is 100 to 1710 times the mole.

Examples of such iodine halides include iodine, bromine iodide, and chloro iodide.

The reaction is usually carried out in the presence of a solvent. The solvent used may be one that does not inhibit the reaction, such as aromatic hydrocarbons such as benzene, toluene, xylene, cumene, trimethylbenzene, and nitrobenzene, chloroform, carbon tetrachloride, dichloroethane, chlorobenzene, and 0-dichlorobenzene. , halogenated hydrocarbons such as bromobenzene, tetrahydrofuran, 1,4-dioxane, 1,3-dioxane, tetrahydrobilane 1,2-methyltetrahydrofuran, ethers such as isopropyl ether, butyl ether, butyl methyl ether, acetonitrile, propio Examples include nitriles such as nitrile and butyronitrile, but halogenated hydrocarbons are preferred.

The method of the present invention is usually carried out by dissolving dichloroacid halide in a solvent and adding phosphorus iodide, silicon iodide, etc., and if iodine halide is used, further adding it. be done.

The reaction temperature is determined by the use of phosphorus iodide, silicon iodide, iodine halide, etc. 4it, although it varies depending on the type etc. usually 40-150°C1 preferably 60-1
20''C.Although the reaction time also varies depending on the amount and type of phosphorus iodide, silicon iodide, iodine halide, etc. used, it is usually about 30 minutes to 20 hours.

The progress of the reaction can be determined by sampling a portion of the reaction solution and analyzing it by gas chromatography, NMR, or the like.

After the reaction, the trans-enriched dichloroacid halide is obtained by one means, such as distillation after removing the catalyst from the reaction mass. It is also possible to derive a low toxicity insecticide by adding 3-phenoxybenzyl alcohol, 5-benzyl-3-furylmethyl alcohol, etc. to the reaction mass and reacting directly without isolation.

It is also possible to directly esterify the reaction mass by adding ethanol etc. and use it as a raw material for biochemical optical resolution, or it can also be derived into a free acid by adding an alkaline aqueous solution etc. and hydrolyzing it according to a conventional method. .

<Effects of the Invention> In this way, the desired trans-dichloroacid halide is produced, and according to the method of the present invention, the trans isomer can be produced under extremely mild conditions compared to known methods.

<Examples> Next, the present invention will be explained in more detail with reference to Examples, but the present invention is not limited to these.

Example 1 After dissolving 1.95 g of dichloroyl chloride consisting of 96.3% cis form and 3.7% trans form in 20 g of chlorobenzene, 260 mg of phosphorus triiodide was added to this under a nitrogen atmosphere.
and 160 mg of iodine were added. This was stirred at 80''C for 6 hours.

After the reaction, cool to room temperature, add 430 mg of ethanol and 750 mg of pyridine, stir at room temperature for 1 hour, and then wash with water.
The solvent was distilled off.

The resulting solution was distilled to a boiling point of 88-90 °C/l m
1.89 g of mHg fraction was obtained. This product was confirmed to be dichloroic acid ethyl ester by infrared absorption spectrum. Analysis by gas chromatography showed that the cis form was 21.1% and the trans form was 78.9%.

Example 2 After dissolving 3.24 g of dichloroyl chloride consisting of 96.6% of cis isomer and 3.4% of trans isomer in 47 g of chlorobenzene, 50 mg of triiodide phosphorus was added to this in a nitrogen atmosphere.
, 150 mg of chloro iodide was added, and the mixture was stirred at 100°C for 6 hours.

After the reaction, the mixture was cooled to room temperature, hydrolyzed using a 15% aqueous sodium hydroxide solution, acidified with 70% sulfuric acid, and extracted with toluene. When the toluene was distilled off, a white solid was obtained.
67g was obtained. This one was confirmed to be dichloroic acid from the infrared absorption spectrum.

A portion was sampled and converted into ethyl ester using a conventional method, and analyzed by gas chromatography. As a result, the cis form was 19.4% and the trans form was 80.6%.

Example 3 Same dichloroyl chloride as used in Example 2 1.05
After dissolving g in 16 g of chlorobenzene, under nitrogen atmosphere, phosphorus triiodide 260+ig and bromine iodide 140 mg
was added and stirred at 100'C for 4 hours.

After the reaction, the reaction mixture was treated in the same manner as in Example 1 to obtain 1.03 g of ethyl dichloroate.

The analysis results were 20.2% cis isomer and 79.8% trans isomer.

Example 4 Same dichloroyl chloride used in Example 1 2.34
g was dissolved in 24 g of chlorobenzene, 330 mg of phosphorus triiodide and 200 mg of iodine were added thereto under a nitrogen atmosphere, and the mixture was stirred at 65°C for 10 hours.

After the reaction, the reaction product was treated in the same manner as in Example 1 and analyzed, and found to be 39% cis-isomer and 61% trans-isomer.

Example 5 Same dichloroyl chloride used in Example 1 1.37
g was dissolved in 26 g of 1,2-dichloroethane, and then 170 mg of phosphorus triiodide and 100 mg of iodine were added to the solution under a nitrogen atmosphere.
mg and stirred at 80°C for 6 hours.

After the reaction, the reaction mixture was treated in the same manner as in Example 1 to obtain 1.30 g of ethyl dichloroate. The analysis result is cis form 25.
7% and trans isomer 74.3%.

Example 6 Same dichloroyl chloride as used in Example 3 930m
After dissolving g in 20 g of 1,4-dioxane, 310 mg of phosphorus triiodide and 190 mg of iodine were added to it under a nitrogen atmosphere.
was added and stirred at 100°C for 4 hours.

After the reaction, the reaction mixture was treated in the same manner as in Example 1 to obtain 856 mg of ethyl dichloroate. The analysis result is cis form 18.
1%, and 81.9% trans isomer.

Example 7 After dissolving 2 g of the same dichloroyl chloride used in Example 1 in 7.5 g of chlorobenzene, 207 mg of silicon tetraiodide and 105 mg of iodine were added thereto under a nitrogen atmosphere, and the mixture was stirred at 80°C for 4 hours. .

After the reaction, the mixture was cooled to room temperature, 526□8 of ethanol and 903 mg of pyridine were added, stirred at room temperature for 1 hour, and then washed with water.
Solvent distillation, boiling point 88-90°C/lmmHg
1.96 g of fraction was obtained.

This product was confirmed to be dichloroic acid ethyl ester from an infrared spectrum.

When the isomer ratio was determined by gas chromatography, it was found that the cis isomer was 17.1% and the trans isomer was 82.9%.

Example 8 After dissolving 2 g of the same dichloroyl chloride used in Example 1 in 18 g of chlorobenzene, 217 n+g of silicon tetraiodide and 61 mg of iodine chloride were added to this under a nitrogen atmosphere.
was added and stirred at 80°C for 4 hours.

After the reaction, the reaction mixture was treated in the same manner as in Example 7 to obtain 1.95 g of ethyl dichloroate.

The analysis results were 17.3% cis isomer and 82.7% trans isomer.

Example 9 After dissolving 2 g of the same dichloroyl chloride used in Example 1 in 18 g of chlorobenzene, 212+ ng of silicon tetraiodide and 122 ng of iodine U were added thereto under a nitrogen atmosphere.
□8 was added and stirred at 80'C for 4 hours.

After the reaction, it was treated in the same manner as in Example 7, and dikuwa 2. 1.86 g of acid ethyl ester was obtained.

The analysis results were 17.3% cis isomer and 82.7% tras isomer.

Example 10 After dissolving 2 g of the same dichloroyl chloride used in Example 1 in 18 g of acetonitrile, 448 mg of silicon tetraiodide and 212B of iodine were added thereto under a nitrogen atmosphere, and the mixture was stirred at 80°C for 4 hours.

The analysis results showed 18% cis isomer and 82% trans isomer.

Example 11 After dissolving 2 g of the same dichloroyl chloride used in Example 1 in 18 g of dichloroethane, 212 mg of silicon tetraiodide and 100 mg of iodine were added thereto under a nitrogen atmosphere, and the mixture was stirred at 80'C for 4 hours.

After the reaction, the reaction mixture was treated in the same manner as in Example 7 to obtain 1.95 g of ethyl dichloroate.

The analysis results were 16.8% cis isomer and 83.2% trans isomer.

Example 12 Same dichloroyl chloride used in Example 1 1.47
g was dissolved in 23 g of chlorobenzene, 140 mg of phosphorus triiodide was added thereto under a nitrogen atmosphere, and the mixture was stirred at 100"C for 8 hours.

After the reaction, the reaction mixture was treated in the same manner as in Example 1 to obtain 1.44 g of ethyl dichloroate.

The analysis results were 45.5% cis isomer and 54.5% trans isomer.

Example 13 2gt- of the same dichloroyl chloride used in Example 1
After dissolving in 8.1 g of chlorobenzene, 198 mg of silicon tetraiodide was added thereto under a nitrogen atmosphere, and the mixture was stirred at 80°C for 4 hours.

After the reaction, the reaction mixture was treated in the same manner as in Example 7 to obtain 2.01 g of ethyl dichloroate.

The analysis results were 27.9% cis isomer and 72.1% trans isomer.

Comparative Example 1 Same dichloroic acid chloride 1.0 as used in Example 2
After dissolving 5 g in 16 g of chlorobenzene, the solution was stirred at 100°C for 8 hours under a nitrogen atmosphere.

The analysis results were 94.7% cis isomer and 5.3% trans isomer.

Claims (2)

[Claims] (1) General formula ▲ Numerical formulas, chemical formulas, tables, etc. ▼ (In the formula, X represents a halogen atom.) Cis or cis/trans mixed 2,2-dimethyl-3-(2,2-dichlorovinyl) )-Trans-2 characterized in that cyclopropanecarboxylic acid halide is reacted with phosphorus iodide or silicon iodide
, 2-dimethyl-3-(2,2-dichlorovinyl)-cyclopropanecarboxylic acid halide. (2) The manufacturing method according to claim 1, which is carried out in the coexistence of an iodine halide.