31 results about "Para-trifluoromethylaniline" patented technology

The invention discloses a method for recycling wastes of trifluoromethyl phenylamine kettle residues. The method comprises the steps of 1) vacuum distillation: by taking the trifluoromethyl phenylamine kettle residues as raw materials, adding inorganic alkali according to the proportion of 2-3% of the mass of the trifluoromethyl phenylamine kettle residues, performing vacuum distillation to obtain a light-component mixture containing m-trifluoromethyl phenylamine and p-trifluoromethyl phenylamine; and 2) vacuum rectification: adding the inorganic alkali into the light-component mixture obtained in the step 1), and performing rectification to obtain m-trifluoromethyl phenylamine and p-trifluoromethyl phenylamine respectively. According to the method disclosed by the invention, a polymerization phenomenon during the process of distillation and rectification is effectively prevented by adopting the inorganic alkali; the method is simple in operation process and easy in industrial production; and by adopting the technical scheme of the method, the discharge of pollutants of the production process is reduced, and the comprehensive recycling of the solid wastes is realized.

The invention relates to a preparation method of teriflunomide. The preparation method comprises the following steps: mixing cyano acetyl chloride, p-trifluoromethylaniline and an acid-binding agent according to the molar ratio of 1:(1-3):(8-11), and reacting to obtain 2-cyano-N-(4-trifluoromethyl-phenyl)-acetamide; mixing 2-cyano-N-(4-trifluoromethyl-phenyl)-acetamide, acetyl chloride and an acid-binding agent according to the molar ratio of 1:(1-5):(1-5) of reaction materials, and reacting to obtain teriflunomide. The process has the advantages that the raw materials are easily available, the reaction condition is mild and the yield is high, and the preparation method is suitable for industrial production.

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.

The invention provides a preparation method of 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)pyrazole. The preparation method takes p-trifluoromethylaniline as a raw material, carries out diazotization reaction and forms a ring with ethyl 2,3-dicyanopropionate under weakly acidic conditions; feeds an appropriate amount of chlorine gas into the ring compound for chlorination , by adjusting the pH decarboxylation to obtain the product 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl) pyrazole. The preparation method of 5-amino-3-cyano-1-(2,6-dichloro-4-trifluoromethylphenyl)pyrazole of the present invention has simple operation, good chlorination selectivity and few side reactions 1. The product yield is high, and the reaction conditions are mild, which is conducive to realizing industrialization; the average yield of the method is not less than 95%, and the product purity is more than 99.50%.