Model reaction for the synthesis of polyhydroxyurethanes from cyclic carbonates with amines: Substituent effect on the reactivity and selectivity of ring-opening direction in the reaction of five-membered cyclic carbonates with amine

This article focuses on the substituent effect on the reactivity and select ivity of the ring-opening direction in the reaction of five-membered cyclic carbonates with n-hexylamine. The reactivity of the cyclic carbonate and t he formation selectivity of the adduct with a secondary hydroxyl group incr eased as a stronger electron-withdrawing group was introduced at the a-meth ylene of the cyclic carbonate. These results are discussed on the basis of the stability of intermediates, primary and secondary alcoholate anions, Mu lliken charges on carbonyl carbon, and the bond lengths and orders of the O -C=O single bond. (C) 2001 John Wiley & Sons, Inc.