Benzylation of Anisole Catalyzed by MoCl5 or MoCl5/Molecular Sieve System

MoCl5 was found as a new catalyst for the benzylation of anisole. In comparison to the general Lewis acid, such as FeCl3, ZnCl2, and AlCl3, the reactivity of MoCl5 was higher than AlCl3 but lower than FeCl3 under the same reaction conditions. When MoC15 was supported on HZSM-5 or TS-1 molecular sieve, the yield of this reaction was increased from 45% to 99% or 98%, and the selectivity of paralortho was promoted from 1: 1 to 1.9:1 or 2.2: 1, respectively. A mechanism of artisole benzylation over MoCl5 was proposed, which was different from the traditional Friedel-Crafts alkylation mechanism.