Production of Difluoroacetic Acid

Introduction

Difluoroacetic acid is mainly used as a pharmaceutical and pesticide intermediate. It can also be used as a new reagent for the C-H difluoromethylation of heteroaromatic compounds. It can also be used in dry etching. and polysilicon have a high selectivity ratio, which can inhibit damage to silicon oxide

Production Methods of CAS 381-73-7 Difluoroacetic Acid

1) Use 2,4,6-tris(difluoromethyl)-s-triazine as raw material

A mixture of 2,4,6-tris(difluoromethyl)-s-triazine and water is heated in the presence of a catalyst such as sodium hydroxide, after separation of unreacted triazine, the acidified aqueous phase is filtered , then extracted with several portions of ether. Difluoroacetic acid can be easily obtained by fractionating the dried ether extract

2) Use dichloroacetic acid as raw material

This reaction is a halogen atom exchange reaction. KF (18 g) was dissolved in 14 mL of water, then dichloroacetic acid (2 g) was added to the above aqueous KF solution, the temperature was raised to 150 °C, and the medium was stirred at 150 °C for 6 min. After returning to room temperature, the aqueous solution was examined by 1H NMR and 19F NMR. The conversion of dichloroacetic acid was 100%, and the yield of difluoroacetic acid was 94%.

3) Preparation of difluoroacetic acid from dichloroacetyl chloride

In the presence of a chromium-based catalyst, dichloroacetyl chloride and hydrofluoric acid are reacted in the gas phase to prepare difluoroacetyl fluoride, and difluoroacetyl fluoride is hydrolyzed to obtain difluoroacetic acid