Method for synthesizing n-hexyl chloroformate by phosgene method

Abstract

The invention discloses a method for synthesizing n-hexyl chloroformate by a phosgene method. The method comprises the following steps: step 1, putting Ag n-hexyl ester into a reaction device at the bottom; step 2, after the temperature of the materials in the reaction device is reduced to the set temperature, introducing phosgene through a flow meter, wherein the cumulative introduction amount ofphosgene is Bg; and performing controlling; step 3, when the phosgene flow is accumulated to Bg, stopping introducing light, heating the material in the reaction device to 28 + / -2 DEG C, and keepingthe temperature for 2 hours; and step 4, after the heat preservation is finished, controlling the temperature to be 15 + / -2 DEG C, and introducing nitrogen to remove excessive phosgene and hydrogen chloride, thereby obtaining the n-hexyl chloroformate product. According to the invention, side reaction generation is inhibited through earlier-stage cooling, the side reaction is effectively inhibitedby a method of heating after the n-hexyl alcohol is gradually consumed and the concentration is reduced, the n-hexyl alcohol is more completely reacted in a later heating manner, the barrel expansionphenomenon caused by the side reaction in a later storage process is greatly reduced and the yield of the n-hexyl chloroformate prepared by the method reaches 97% or above.

Description

technical field [0001] The invention belongs to the field of chemistry, and in particular relates to a method for synthesizing n-hexyl chloroformate by a phosgene method. Background technique [0002] N-hexyl chloroformate is a chemical product with the formula C 7 h 13 ClO 2 , is mainly used as a reagent for organic synthesis, and is a raw material for many medicines. At present, there is no preparation method for n-hexyl chloroformate in China, and it is completely dependent on imports. And when producing by phosgene method abroad, usually whole reaction temperature keeps constant, but the product impurity content of making like this is more, and product yield is lower. Because n-hexanol will react with the product n-hexyl chloroformate to generate di-n-hexyl carbonate: [0003] side effects [0004] CH 3 (CH 2 ) 5 OH+CH 3 (CH 2 ) 5 OCOCL → [0005] CH 3 (CH 2 )5 OCOO(CH 2 ) 5 CH 3 (di-n-hexyl carbonate) + HCL. Contents of the invention [0006] Aiming...

AI Technical Summary

Problems solved by technology

At present, there is no preparation method for n-hexyl chloroformate in China, and it is completely dependent on imports

However, when producing by the phosgene method in foreign countries, the entire reaction temperature is usually kept constant, but the product produced in this way has more impurities and a lower product yield.