JPS6029376B2 - Production method of trans chrysanthemum acid chloride - Google Patents

Description

[Detailed description of the invention] The present invention relates to a method for producing trans chrysanthemum acid chloride.

More specifically, the present invention is an industrially advantageous method for producing trans chrysanthemum acid chloride, which is characterized by reacting cis chrysanthemum acid chloride at a temperature below room temperature using a boron halide as a catalyst. Conventionally, regarding the industrial production method of trans chrysanthemum acid chloride, cis chrysanthemum acid chloride is
A method of heating in a temperature range up to 00 qo is known (Japanese Patent Publication No. 47-126778).

However, chrysanthemum chloride N is generally unstable to heat and suffers from significant thermal deterioration at such high temperatures, which poses a problem for industrial implementation. Furthermore, it is said that trans conversion hardly occurs at temperatures below 10 p0.
No. 7-26778). However, the present inventors have researched a method for producing trans chrysanthemum chloride, and found that cis chrysanthemum chloride can be isomerized to trans chrysanthemum chloride very easily and in high yield by using boron halide as a catalyst. This is what I discovered.

This has the effect of making the industrial production of trans chrysanthemum acid chloride extremely advantageous. It is well known that chrysanthemum chloride is derived from chrysanthemum chloride with various arthropod activities, and esters derived from trans chrysanthemum chloride have better effects than esters derived from cis or cis-trans mixtures. This is a fact. To explain the method of the present invention in more detail, by using a halogenated shelf as a catalyst for trans-transforming cis-chrysanthemum acid chloride, the reaction temperature can be lowered to room temperature or lower, usually from -70 qo to 20 qo.
The trans transformation can be carried out very quickly and in high yields at temperatures of qo.

When carrying out the reaction, it is preferable to dilute with a solvent that does not coagulate in the temperature range of this reaction and does not essentially inhibit the transconversion reaction, to give preferable results. Examples of the solvent include aromatic hydrocarbons and derivatives thereof such as toluene, xylene, and chlorobenzene, aliphatic hydrocarbons such as bentane, hexane, heptane, and cyclohexane, and halides such as carbon tetrachloride, chloroform, and methylene dichloride. Alternatively, it is also possible to use a mixed solvent of these. The reaction is carried out by bringing the boron halide catalyst into contact with these reaction systems. Examples of the halogenated elements include chloride, bromide, and fluoride, and chloride gives particularly favorable results when used industrially. The amount of catalyst used is 1'20 per mole of cis-chrysanthemum chloride to be treated.
00 to 1/2 mol, preferably 1/200 to 1/5
It is a mole. The time required for the reaction may vary depending on the amount of catalyst used and the reaction temperature, but usually 0.1 minute to 3 hours is sufficient to achieve the purpose.

The process of the invention can be carried out either batchwise or continuously.

Cis chrysanthemum acid chloride can be added to the reaction vessel together with the catalyst in a single introduction, or if desired, it can be added continuously or intermittently to the reaction vessel as the reaction progresses. Needless to say, even when the method of the present invention is applied to a mixture of cis and trans chrysanthemum chloride, trans chrysanthemum chloride can be obtained with similar results.

The progress of the reaction can usually be determined by analysis using gas chromatography.

After the reaction is completed, the catalyst is deactivated and removed, and then subjected to conventional vertical distillation to obtain chrysanthemum acid chloride through trans conversion. This product is free from alcohol such as pyrethrolone and arethrolone. It is possible to directly induce an insecticidal ester by reacting it in the presence of a hydrogenation agent. Furthermore, after trans-conversion, an alkaline aqueous solution is added as in a conventional method to carry out hydrolysis, and then neutralized with key acid, it is possible to obtain a trans-converted carboxylic acid. Next, the method of the present invention will be explained with reference to Examples.

Example: Put 30.0 g of cis-1 chrysanthemum chloride and 70 g of toluene into a 1200-gold flask, and add 50.0 g of toluene to a flask of 1200 g.
At ~10°C, 0.85 g of trichloride was added and reacted for 10 minutes with candlelight.

A portion of the reaction solution was collected and analyzed by gas chromatography, and the results were as follows. Trans chrysanthemum acid chloride 91
．． 3%, cis chrysanthemum acid chloride 8.7%.

After removing the catalyst, the toluene was concentrated and recovered, and distilled to yield 27.5 g of trans-transformed chrysanthemum acid chloride with a boiling point of 73 to 78 0/2 Hg. After hydrolysis with an aqueous caustic soda solution in the usual manner, trans-transformed chrysanthemum acid was obtained by neutralizing the product with an aqueous sulfuric acid solution. m. p. There were 5 to 54 ○. Example 2 Cis, trans mixed primary chrysanthemum chloride (35% cis form,
The reaction was carried out in the same manner as in Example 1 using 30% trans-isomer (65% trans isomer) at 5 to 1000 for 5 minutes.

When analyzed by gas chromatography, trans isomer 91.
3%, and cis form 8.7%. The mixture was treated in the same manner as in Example 1 to obtain 27.9 g of trans-transformed chrysanthemum chloride. Example 3 10.0% of cis-stochrylate chloride in a 200ml flask
9M of n-hexane and 9M of n-hexane were added, and 0.25% of trichloride was added at 0°C under a nitrogen atmosphere, and the mixture was allowed to react for 20 minutes while stirring.

A portion of the reaction solution was collected and analyzed by gas chromatography, and the results were as follows. After removing the catalyst (91.9% trans isomer and 8.1% cis isomer), the n-hexane is concentrated and recovered, and when distilled, the boiling point is 5000/0.5 Hg~5 G○
9.4 hours of trans-transformed chrysanthemum acid chloride with a concentration of /0.6 hours Hg was obtained.

Example: In the flask above 4200, mixed cis and trans primary chrysanthemum chloride (35% cis form, 65% trans form)
Add 30 liters of carbon tetrachloride and 70 liters of carbon tetrachloride, and heat for 10 liters under nitrogen atmosphere.
00, 1.6 ml of tribromine tribromine was added, and the reaction was allowed to proceed for 3 minutes while keeping an eye on the mixture.

After removing the catalyst, the solvent was collected.

The concentrated solution was hydrolyzed by a conventional method to obtain daisies chrysanthemum acid. The yield was 25.7 days, and analysis by gas chromatography showed that the trans isomer was 91.2% and the cis isomer was 8.8%. Example: In a 5200' flask, cis and trans mixed primary chrysanthemum chloride (35% cis form, 65% trans form) was added.
%) and toluene 902 were added, and while cooling to about 17,000, chlorine trifluoride was added and reacted.

After 6 minutes, the reaction solution was analyzed by gas chromatography and found to be 97.5% trans-isomer and 2.5% cis-isomer.

Claims (1)

[Claims] 1. A method for producing trans chrysanthemum chloride, which comprises reacting cis chrysanthemum chloride or a mixture of cis and trans chrysanthemum chloride at a temperature of about 20° C. or lower using a boron halide as a catalyst.