The control mechanism of (BisSalen)Al-mediated asymmetric kinetic resolution polymerization of phenethylglycolide

Abstract

Chiral (BisSalen)Al complexes have been confirmed as powerful catalysts for perfect asymmetric kinetic resolution polymerization (AKRP) of racemic phenethylglycolide (Pegl). However, understanding of the control mechanism in the AKRP mediated by (BisSalen)Al complexes is not sufficient. Herein, the polymerization of diastereomeric (rac- and meso-) Pegl mixtures mediated by (BisSalen)Al complex SS-1 was investigated for the first time. The origin of the AKRP of Pegl was determined to be enantiomorphic site control (ESC) using NMR-HPLC analysis, kinetic studies and stereosequence analysis.