Preparation method of (8E, 10E)-8, 10-dodecadienol-1-alcohol

Abstract

The invention discloses a preparation method of (8E, 10E)-8, 10-dodecadienol-1-alcohol. The method comprises the steps of: reacting 6-chlorohexanol with trimethylchlorosilane in the presence of methyl tertiary butyl ether and triethylamine at 0 to 5 DEG C to obtain chloride trimethylethoxysilane; then performing the Grignard reaction on the chloride trimethylethoxysilane to obtain a Grignard agent; and reacting (2E, 4E)-2, 4-hexadiene-1-dryocrassyl acetate with the Grignard agent to obtain (8E, 10E)-8, 10-dodecadienol-1-triethoxysilane; and finally hydrolyzing the (8E, 10E)-8, 10-dodecadienol-1-triethoxysilane to obtain (8E, 10E)-8, 10-dodecadienol-1-alcohol. According to the preparation method, both the purity and the yield of hydroxy-protecting reaction product are relatively high; and the initiating success rate of the Grignard reaction is relatively high, the purity of the coupling reaction product is high.

Description

technical field [0001] The present invention relates to a preparation method of sex pheromone, in particular to a preparation method of (8E,10E)-8,10-dodecadien-1-ol. Background technique [0002] (8E,10E)-8,10-dodecadien-1-ol is the chemical name for the codling moth sex pheromone. [0003] Chinese patent document CN101440020A discloses a preparation method of (8E,10E)-8,10-dodecadien-1-ol, the method has the following steps: 1. Mix chlorohexanol and trimethylchlorosilane in alkali; The reaction time is 3h~9h, the reaction temperature is 25℃~35℃, and then post-treatment is carried out to obtain chlorohexyloxytrimethylsilane; ②The post-treated chlorohexyloxytrimethylsilane obtained in step ① Methylsilane obtains Grignard reagent through Grignard reaction; ③ in Li 2 CuCl 4 In the presence of a catalyst, (2E,4E)-2,4-hexadien-1-ol acetate is coupled with the Grignard reagent obtained in step ②, and the temperature of the catalytic reaction is controlled by ice brine to -15°C...

AI Technical Summary

Problems solved by technology

[0004] The disadvantages of this method are: (1) The temperature of the hydroxyl protection reaction in step ① is 25°C to 35°C, which is easy to produce impurities, and finally leads to the low purity of the product chlorohexyloxytrimethylsilane (only 96%)

In addition, due to the hydrolysis reaction of trimethylchlorosilane in sodium carbonate solution, part of trimethylchlorosilane cannot react with chlorohexanol, resulting in low yield of this step (according to the embodiment with the largest yield 1 calculation, the actual yield is only 88%)

(2) The Grignard reaction in step ② uses iodine as the initiator, and directly uses chlorohexyloxytrimethylsilane to react and add it at one time. Since the Grignard reaction is very violent, this reaction method leads to the success of the Grignard reaction. Very small rate

In terms of reaction kinetics, this feeding method will make the catalytic ability very strong, which will lead to the formation of more impurities

In addition, higher dropping temperature and higher catalyst concentration (above 0.2mol / L) also easily lead to the formation of more impurities

The generated impurities are difficult to remove, so the purity of the product of the coupling reaction is not high, which in turn affects the purity of the final product (8E,10E)-8,10-dodecadien-1-ol