Method for synthesizing trifluoromethyl amine

Abstract

The invention discloses a method for synthesizing trifluoromethyl amine. The method comprises the following steps of: mixing amino acid, anhydrous hydrofluoric acid and sulfur tetrafluoride in a molar ratio of 1:(3-20):(1.8-3.2), and reacting at temperature of between 50 and 150 DEG C for 2 to 10 hours; and cooling, neutralizing, extracting and rectifying to obtain a trifluoromethyl amine product. According to the method, a process is short; and the product is easy to separate, high in yield and stable in quality, the highest yield is 88 percent, and the content of the product is over 97.5 percent.

Description

technical field [0001] The invention relates to the technical field of fluorine fine chemical industry, in particular to the preparation of trifluoromethyl-containing compounds. Background technique [0002] Trifluoromethyl amine compounds are important intermediates in organic synthesis, mainly used in organic synthesis, pharmaceutical and pesticide intermediates, and also intermediates in liquid crystal synthesis. [0003] The method for preparing trifluoromethyl amine mainly contains the following: [0004] 1) Platinum-catalyzed hydrogenation of fluorocarbonnitriles produces 1,1-dihydroalkylamines. For example, use this method to convert CF 3 CN reduction to CF 3 CH 2 NH 2 , the yield was 80%. The disadvantage is that the raw material fluorocarbon nitrile is relatively expensive and is not suitable for large-scale industrial production. [0005] 2) Ammonolysis of halogens other than fluorine in trifluoromethyl-containing compounds with ammonia to generate trifluoro...

AI Technical Summary

Problems solved by technology

The disadvantage is that the raw material fluorocarbon nitrile is relatively expensive and not suitable for large-scale industrial production

The disadvantage is that the product obtained by this method exists in the form of hydrochloride, which needs to be purified under alkaline conditions, and the post-treatment is more complicated

[0006] 3) Hexafluoroacetone reacts with chiral benzylamine to produce N-(1,1,1-trifluoroisopropylidene)benzylamine, which is then reacted with primary amine to obtain trifluoroisopropylamine (US6166259), with a total yield of 35%, the method steps are cumbersome, the yield is low, and the raw material hexafluoroacetone is relatively expensive, so it is not suitable for large-scale industrial production

The method has high yield and simple reaction, but the raw materials used are not easy to obtain