Preparation method of 2, 2-difluoroethanol

Abstract

The invention provides a preparation method of 2, 2-difluoroethanol. The preparation method comprises the steps as follows: when an organic solution is neutralized to the temperature of subzero 20 DEG C-0 DEG C, methyl difluoroacetate or ethyl difluoroacetate is taken as a raw material, lithium aluminum hydride is taken as a reducing agent, and high-yield and high-purity 2, 2-difluoroethanol is obtained. The method is simple and convenient and can be applicable to large-scale industrial production, and the raw material is easy to obtain.

Description

technical field [0001] The invention relates to a preparation method of 2,2-difluoroethanol, which is a method capable of adapting to large-scale industrial production of 2,2-difluoroethanol. Background technique [0002] After decades of hard work, organic fluorine chemical industry has established a good foundation and scale in my country, and the production scale of some fluorine-containing basic raw materials is already the first in the world, such as: anhydrous hydrofluoric acid, HCFC-22, HFC-134a, tetrafluoroethylene monomer, hexafluoropropylene, etc. Fluorine-containing fine chemical products are an important branch of organic fluorine chemicals. Due to their variety, high added value and high technical content, they are attracting more and more investment interest from production enterprises. Among them, aliphatic fluorine-containing intermediates can be used in the synthesis of surfactants, fabric finishing agents, new pharmaceutical and pesticide synthetic raw mate...

AI Technical Summary

Problems solved by technology

[0005] Using 1,1-difluoro-2-bromo (or chloro)ethane as a raw material, there are many reaction steps and a long time, resulting in a decrease in its total yield

[0006] Using difluoroacetyl chloride as the starting material is the main method of industrial production at present, the reaction reagent is easy to obtain, and the catalyst can be recycled; but the catalyst is expensive and the yield is not high, which increases the production cost

[0007] Using difluoroacetic acid or difluoroacetic acid ester as the starting material, the reaction is relatively simple, especially when difluoroacetic acid ester is used as the starting material, only borohydride is used as the reducing agent during the reaction, no other additives are required, and the reagent price Cheap and easy to obtain, high yield, greatly reducing production costs; but the post-reaction treatment of difluoroethanol is relatively difficult, and there is no literature report on the purification and separation method in industrial production, resulting in this preparation method only in small-scale laboratories It is used in preparation, but there are still some problems in the application of industrial production.

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