High-efficiency simple synthetic method for delta-chlorobutyl ester

Abstract

The invention provides a preparation method for delta-chlorobutyl ester. A key point of the invention is as follows: tetrahydrofuran is used as a raw material to react with acyl chloride under catalysis of zinc chloride so as to rapidly and mildly synthesize delta-chlorobutyl ester with high yield and high purity. According to the invention, reduced pressure distillation and purification are directly carried out under the condition of no separation; unfavorable factors of low yield, long reaction time, excess usage amount of raw materials, need for expensive catalysts, severe reaction conditions and the like in conventional methods are avoided; the method is characterized by no use of a solvent or use of a small amount of the solvent, a small catalyst usage amount, a low price, mild reaction conditions and high yield; the whole process of preparation is simple and safe and costs little, and the method is applicable to industrial mass production.

Description

Technical field: [0001] The invention belongs to the field of fine chemical industry and relates to a preparation method of delta-chlorobutyl ester. technical background: [0002] δ-Chlorobutyl ester is widely used in the synthesis of natural products containing 4 carbon atom chains, medicine, etc., and is an important intermediate in the synthesis of many compounds. It has long been noticed that in Lewis acids such as ZnCl 2 、BCl 3 , bismuth halides, organic lanthanum complexes and iodine, etc., tetrahydrofuran can crack and open the ring. But the reported method has many deficiencies, such as low yield, high cost or difficult to obtain reagents, some methods require long reaction time, harsh reaction conditions, need to use solvents and react under reflux conditions, use environmentally harmful Catalysts and very cumbersome methods. Therefore, finding a new method for preparing δ-chlorobutyl ester has very important practical significance. Jone Cloke etc. (JACS 1939,2...

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Problems solved by technology

Jone Cloke etc. (JACS 1939,2667-2669) report THF and different acyl chlorides ring-opening method to generate a series of δ-chlorobutyl esters under the catalysis of zinc chloride, but the method yield is low, and the reaction reflux time is long, requiring excess acid chloride

Pasha M.A. et al. (Ultrasonics sonochemistry, 2006, 175-179) used zinc powder as a catalyst to obtain δ-chlorobutyl ester with high yield under the action of ultrasonic waves, but the use of zinc powder and ultrasonic waves is not conducive to industrial production

Pasha M.A. et al. (synthetic communication, 2007, 927-932) used iodine as catalyst tetrahydrofuran and acyl chloride to generate δ-chlorobutyl ester in high yield at room temperature. Tetrahydrofuran, but also to remove iodine with sodium thiosulfate, after-treatment is cumbersome, not suitable for industrial production

Yadav J.S., Suresh V., etc. used InBr (Journal of molecular Catalysis A: chemical, 2007, 266-269), Bi(NO 3 ) 3 (Canadian Journal of chemistry, 2007, 1037-1040), La(NO 3 ) 3 (synthetic communication2008, 92-99) etc. as catalysts, acid chlorides successfully ring-open tetrahydrofuran to generate δ-chlorobutyl esters, but these catalysts are relatively expensive

Field et al. (JACS 1995,77,1206-7) have reported the method for preparing 4-chlorobutyl p-toluenesulfonate, but the method yield is low (34%), the temperature is high, the reaction time is long, and the reaction is too high at the beginning. too severe, dangerous

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