An efficient palladium catalyst system for the oxidative carbonylation of glycerol to glycerol carbonate.

Glycerol carbonate can be readily synthesized from the oxidative carbonylation of glycerol catalyzed by PdCl(2)(phen) (phen=1,10-phenanthroline) with the aid of CuI. High conversion (95 %) and selectivity (98 %) are achieved and the turnover frequency (TOF) reaches 455 h(-1). Furthermore, a new zeolite-Y-confined Pd catalyst, PdCl(2)(phen)@Y, has been successfully prepared by a ''flexible ligand'' method. The structure and composition of the heterogeneous catalyst have been characterized by atomic absorption spectroscopy, elemental analysis, N(2) sorption, XRD, FTIR, solid-state NMR, and X-ray photoelectron spectroscopy. This catalyst exhibits a comparable activity to its homogeneous counterpart and could be reused five times without significant decrease in activity. This is the most efficient heterogeneous system for synthesizing glycerol carbonate by the oxidative carbonylation of glycerol to date.