Palladium-lead catalyzed oxidative carbonylation of phenol

Oxidative carbonylation of phenol to form diphenyl carbonate (DPC) was examined. A novel catalyst of type Pd-Pb-NMe4Br was found to show high activity and selectivity for the present reaction. The Pd species seems to work as an homogeneous catalyst. The rate of DPC formation was in first order with respect to P-O2 and [Pb], indicating that the oxygen activation with lead compound is the rate-determining step. Concomitant bromophenol formation was suppressed by Cu or Co additives and longer catalyst life was achieved with these additives. (C) 1998 Elsevier Science B.V.