Zinc(II)-pyridine-2-carboxylate / 1-methyl-imidazole: A binary catalytic system for the synthesis of cyclic carbonates from carbon dioxide and epoxides

Abstract

A new "halogen-free" binary catalytic system for the synthesis of cyclic carbonate from epoxides and carbon dioxide is described. The catalysis relies on a synergy between the main catalyst, zinc(II) pyridine-2-carboxylate, and a Lewis base, 1-methyl imidazole. In this preliminary study four epoxides have been tested and the operating capabilities of this system have been evaluated. Using propylene oxide as test substrate and performing the catalysis in a high-pressure NMR tube, allowed us to gather some spectroscopic information on this catalytic system and to propose a reaction mechanism. ©ARKAT-USA, Inc.