Synthetic method of p-trifluoromethylaniline

Abstract

The invention relates to a synthetic method of p-trifluoromethylaniline; p-chlorobenzotrifluoride and liquid ammonia generate an ammonolysis reaction to generate the p-trifluoromethylaniline under the action of a catalyst and an acid-binding agent; according to portion by weight, the components of the catalyst is: cuprous chloride of 1 to 10 portions, potassium fluoride of 2 to 30 portions and phase transfer catalyst of 5 to 30 portions; the adding amount of the catalyst is 8 to 70 percent of the p-chlorobenzotrifluoride (mass); the synthetic method of the invention adopts an effective compound catalyst to provide a synthetic scheme which has higher one way conversion rate and is economically practical in industry for the synthesis of the p-trifluoromethylaniline; the price of the catalyst used in the synthetic process is lower; furthermore, an organic solvent and the phase transfer catalyst can be recycled and reused; the manufacture cost is low; no waste water is discharged during the whole technique process; and the synthetic method of the invention is friendly to the environment.

Description

technical field [0001] The invention belongs to the technical field of organic synthesis, in particular to a synthesis method of p-trifluoromethylaniline. Background technique [0002] p-Trifluoromethylaniline is one of the important fine chemical products, which can be used to synthesize a variety of pesticides. With the deepening of research on new varieties of pesticides, its application range is becoming wider and wider. The product is chlorinated to obtain 2,6-dichloro-p-aminotrifluorotoluene, which is an important pesticide intermediate and is used in the pesticide industry to synthesize insecticides fipronil (fipronil) and fluoramine cyprothrin, flunzafenuron, fungicide fluazinam, herbicide butaflurane, etc. Among them, due to the introduction of fluorine-containing groups into its structure, fipronil has many outstanding advantages such as high efficiency, low toxicity, and low residue. [0003] There are many synthetic methods of p-trifluoromethylaniline, and ther...

AI Technical Summary

Problems solved by technology

[0004] US4096185 has proposed with p-chlorobenzotrifluorotoluene raw material, and cuprous chloride is cocatalyst, and potassium fluoride is main catalyst direct high-pressure ammonolysis and prepares the method for p-aminobenzotrifluorotoluene, but, there is following shortcoming in this method: (1) fluorine Potassium chloride consumption is high, and the process is uneconomical; (2) it is difficult to obtain higher selectivity while ensuring a higher p-chlorobenzotrifluoride conversion; (3) the reaction temperature is high, and the process energy consumption is high

[0005] Chinese patent 200610040453.2 discloses a method of directly high-pressure ammonolysis of p-chlorobenzotrifluoride to synthesize p-aminobenzotrifluoride. Although the conversion rate of the ammonolysis reaction is relatively high, there is still the problem of relatively high catalyst prices