Oxidative carbonylation of phenol to form diphenyl carbonate (DPC) was inve
stigated in the multi-step electron transfer system containing homogeneous
or heterogeneous palladium as the main component. Carbon-supported Pd catal
yst showed a better DPC yield than the best homogeneous system with Pd(OAc)
(2) for the same amount of palladium. For the supported palladium catalyst,
the hydrophobicity of the supports appeared to be critical for high yields
of DPC. The palladium remained in the metallic state and dissolution into
the reaction solution was, if there was any, negligible. Effects of promote
rs in carbon-supported Pd catalyst system were also examined. (C) 2000 Else
vier Science B.V. All rights reserved.