Benzene oxidation with hydrogen peroxide catalyzed by soluble and heterogenized copper compounds

Copper(II) salts (acetate, perchlorate, and chloride) catalyze the oxidation of benzene with hydrogen peroxide in an acetonitrile solution to give phenol and quinone. The initial rates, the yield of products, and the phenol: quinone ratio depend on the salt chosen and on the presence of 2,2'-dipyridyl as an additive. For example, catalysis by copper perchlorate in the presence of 2,2'-dipyridyl at 50 degrees C results in the formation of phenol and quinone with a yield of 12.5 and 1.5%, respectively (the turnover number reaches 1900). Copper chloride coordinated to solid polymers, poly(4-vinylpyridine) or poly(4-methyl-4'-vinyl-2,2'-dipyridyl), also acts as a catalyst for benzene oxidation into phenol and quinone. It was shown that the catalysis is mediated by the copper ions on the surface of the solid support. The heterogenized catalyst may be reused with some loss of activity.