Synthesis and Cyclohexene Oxide/Carbon Dioxide Copolymerizations of Zinc Acetate Complexes Bearing Bidentate Pyridine‐Alkoxide Ligands

Abstract

AbstractSummary: The reaction of 2‐lithio‐6‐methylpyridine or 2‐lithiopyridine and the appropriate diaryl ketone followed by hydrolysis yields 6‐Me‐pyCAr2OH pyridine alcohols or pyCAr2OH pyridine alcohols. The reactions of zinc acetate with 1 equiv. of the lithiated products of the ligands proceed rapidly to afford LiOAc salt and mono‐ligand complexes (6‐Me‐pyCAr2O)Zn(OAc) and (pyCAr2O)Zn(OAc), respectively, in high yield. The copolymerizations of carbon dioxide with cyclohexene oxide were investigated. The (6‐Me‐pyCAr2O)Zn(OAc) showed moderate yield and CO2 incorporation. The [6‐Me‐pyC(4‐Cl‐C6H4)2O]Zn(OAc) complex gave large polymers with high proportions of carbonate linkage (>60%) and narrow polydispersity, indicating single active sites.The monoligated Zn complexes synthesized and used here as catalysts for the copolymerization of cyclohexene oxide and carbon dioxide.imageThe monoligated Zn complexes synthesized and used here as catalysts for the copolymerization of cyclohexene oxide and carbon dioxide.