Diphenyl Oxalate Synthesis from Transesterification of Dimethyl Oxalate with Phenol over TiO_2/Al_2O_3 Catalyst

摘要

Diphenyl carbonate (DPC) is a basic material for non-phosgene production of polycarbonates. Several alternative non-phosgene methods for DPC synthesis have also been proposed. Among them, transesterification of dimethyl oxalate (DMO) with phenol is conducted following the step of transesterification of DMO with phenol to prepare diphenyl oxalate (DPO) as well as decarbonylation of DPO to DPC. Thereinto, the synthesis of DPO from transesterification of phenol with DMO follow a 2-step reaction module consisting of transesterification of DMO with phenol into methyl phenyl oxalate (MPO) and disproportionation of MPO into DPO and DMO. TiO_2/Al_2O_3, as a heterogeneous catalyst, showed excellent selectivity of MPO and DPO compared with other conventional ester exchange catalysts.