Transesterification of dimethyl carbonate and phenol to diphenyl carbonate with the bismuth compounds

Bismuth oxide was first employed for the transesterification of dimethyl carbonate with phenol to diphenyl carbonate, which has excellent catalytic activity. With 0.4 g Bi2O3, the phenol conversion of 46.4% and transesterification selectivity of 99.9% were attained. The characterization of the used sample by XRD, FTIR and solid-state C-13-NMR indicate that a new compound of bismuth phenoxide was formed with the disappearance of bismuth oxide. It was evidenced that the bismuth phenoxide act as the role of active phase in the transesterification, which was generated facilely in situ by the reaction of bismuth oxide added with the raw material of phenol. The bismuth phenoxide presents excellent reusability, after four consecutive runs, the phenol conversion remained above 45%, and the transesterification selectivity was maintained at 99.9%.