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

Abstract

The chiral (BisSalen)Al complexes have been confirmed as powerful catalysts for perfect asymmetric kinetic resolution polymerization (AKRP) of racemic phenethylglycolide (Pegl). However, 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 AKRP in Pegl was determined to be enantiomorphic site control (ESC) through NMR-HPLC analysis, kinetic study and stereosequence analysis.