| 摘要 |
PURPOSE:To prepare p-alkylchlorobenzene useful as a raw material of pharmaceuticals, agricultural chemicals, and various organic syntheses, in high selectivity, by chlorinating alkylbenzene using a specific chemically modified silica gel as a catalyst. CONSTITUTION:The objective compound is prepared by reacting an alkylbenzene such as cumene, toluene, ethylbenzene, etc., with a chlorinating agent, preferably chlorine gas, at 0-80 deg.C under normal pressure, in the presence of a chemically modified silica gel catalyst of formulaI(A is silica gel; R is alkyl; n is 1-2), thereby chlorinating the p-position of the alkylbenzene. The chemically modified silica gel can be prepared by reacting the silica gel for column chromatography with 3-(N-alkyl)amino-propyltriethoxysilane in an inert solvent, and reacting the resultant compound of formula II with the nitrobenzoic acid halide of formula III (X is halogen) in an inert solvent in the presence of a dehydrochlorinating agent. |
