Polymer-Supported Tetrabromooxomolybdate(V): A New Type of Catalyst for Oxidation by t-Butyl Hydroperoxide

Tetrabromooxomolybdate(V) was immobilized in alkylammonium cation-type polymers obtained by the reaction of poly(p-chloromethyl-styrene-co-divinylbenzene-co-styrene) (abbreviated CMS) with amines and derived from poly(p-vinylpyridine) and poly(p-vinylpyridine-co-divinylbenzene). These immobilized polymers were active catalysts for the oxidation of alcohols and epoxidation of olefins with t-butyl hydroperoxide (abbreviated t-BuOOH). Among these polymers, we could find a polymer catalyst showing specificity, which was obtained by immobilization of tetrabromooxomolybdate(V) in the polymer derived from the reaction of CMS with trimethylamine. This immobilized polymer does not catalyze epoxidation of olefins but catalyzes oxidation of alcohols with t-BuOOH. Ammonium tetrabromooxomolybdate(V) complex was stabilized by the immobilization in the polymers, and it was found that the reactivity of the active group is due to the microenvironment supplied by the polymer chain.