Oxidation of cyclohexane by transition metal oxides on zeolites

Abstract

Transition metals (Co, Mn, Fe, and Cu) were deposited as the hydrated oxides on a series of zeolites (Y, β, ZSM-5, mordenite, and ferrierite) and examined for activity for the oxidation of cyclohexane at 70°C and ambient pressure. The materials that demonstrated catalytic activity under these extremely mild conditions were the cobalt-based catalysts. The copper and copper/iron materials demonstrated stoichiometric activity for the oxidation of cyclohexane to cyclohexanol and cyclohexanone. The cobalt-based catalysts produced the intriguing products caprolactone, 1-hexanol, and 3-methyl-1-pentanol, as well as the expected cyclohexanol and cyclohexanone. Of most interest was the production of 1-hexanol, indicative of novel activity in the oxidative ring cleavage and oxidation of cyclohexane. © Riley et al.