氯代苯胺液相催化加氢合成环己酮

Abstract

A method for the degradation of chloraniline for high selective synthesis of cyclohexanone was proposed. The cyclohexanone was synthesized from multichloraniline (2,4,6-trichloroaniline and 2,4-dichloroaniline) with a high selectivity (without cyclohexanol) over a La modified Pd/Al2O3 catalyst. The conversion of the hydrogenation of 2,4,6-trichloroaniline and 2,4-dichloroaniline are both 100%, and the corresponding selectivity of cyclohexanone are 98.6% and 100% (cyclohexanol was not detected), respectively, under the optimal reaction conditions. Chloraniline was first underwent hydrodechlorination/ N -methylation reactions to form intermediates such as aniline, N -methylaniline, N , N -dimethylaniline, etc. on the surface of the Pd/La-Al2O3 catalyst. Then cyclohexanone was produced from the ring hydrogenation and amino-group hydrolysis/alcoholysis of these intermediates. The presence of Cl in the chloraniline molecular and water in the reaction system is important for the selectivity of cyclohexanone.