DFT studies on the origin of regioselective ring-opening of terminal epoxides during copolymerization with CO2

Abstract

This report presents a detailed density functional theory (DFT) study on the difference in regioselectivity for the copolymerization reactions of styrene oxide versus propylene oxide with CO2 utilizing binary (salen)cobalt(III) catalyst systems. This study focuses on the discrepancy of regioselective ring-opening of two terminal epoxides during the copolymerization with CO2. It was found that the nucleophilic ring-opening of styrene oxide occurred predominantly at the methine C α -O bond due to the election delocalization of phenyl group to stabilize the transition state for the methine C―O bond cleavage.