Method for producing 2,6-dichloro-4-trifluoromethylaniline

Abstract

The present invention discloses 2, 6-dichloro-p-trifluoro methyl aniline preparing process, which includes the first reaction of 3, 4, 5-trichloro trifluoro toluene and fluoride salt in solvent to produce 3, 5-dichloro-4-fluoro trifluoro toluene, and the subsequent reaction of 3, 5-dichloro-4-fluoro trifluoro toluene and liquid ammonia or ammonia water to obtain 2, 6-dichloro-p-trifluoro methyl aniline. The process has 3, 4, 5-trichloro trifluoro toluene as the side product from p-chloro trifluoro toluene producing process adopted, lowered production cost, no use of acid matter and less corrosion of the equipment.

Description

technical field The invention relates to a preparation method of 2,6-dichloro-p-trifluoromethylaniline. Background technique 2,6-Dichloro-p-trifluoromethylaniline is a chemical intermediate of medicine and pesticide, which is widely used in the fields of medicine and pesticide. At present, there are mainly the following preparation methods: The most direct method is, p-trifluoromethylaniline reacts with chlorine to generate 2,6-dichloro-p-trifluoromethylaniline, such as documents EP34402, EP639,556, but the preparation process of p-trifluoromethylaniline is complicated and the operation Conditions are harsh and products are expensive. Document Fr1,545,142 discloses a method for preparing 2,6-dichloro-p-trifluoromethylaniline by hydrolysis of 2,6-dichloro-p-trifluoromethylbenzene isocyanate in concentrated sulfuric acid, but in fact 2,6 -Dichloro-p-trifluoromethylbenzene isocyanate is more difficult to prepare than 2,6-dichloro-p-trifluoromethylaniline. Document EP599,...

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Problems solved by technology

Document EP599,704 discloses to use p-chlorobenzotrifluoride or 3,4-dichlorobenzotrifluoride as raw material to prepare N,N-dimethyl-2,6-dichloro-p-trifluoromethylaniline and then chlorinate Process for obtaining 2,6-dichloro-p-trifluoromethylaniline, which has the disadvantage of the pressure in the autoclave for the preparation of the starting material N,N-dimethyl-2,6-dichloro-p-trifluoromethylaniline It is difficult to control and may even explode out of control. In addition, the equipment is severely corroded during chlorination, and the product is difficult to purify

In summary, the above methods are either expensive in raw materials, or have great disadvantages, so it is necessary to find another preparation method

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