title: Ring-opening polymerization of L-lactide catalyzed by calcium complexes.
abstract: A series of calcium complexes supported by NNO-tridentate ketiminate ligands have been synthesized and characterized. X-ray structural studies indicate that these complexes bear a mononuclear feature with hexa-coordinated calcium centers bonding to two ketiminate ligands. Polymerization of L-lactide catalyzed by these complexes proceeds rapidly and well controlled in the presence of a variety of alcohols. In addition, these complexes reveal good catalytic activity even with the addition of up to 80 equiv. of benzyl alcohol as a transfer agent. Furthermore, kinetic studies show ROP of L-lactide is a first-order dependency on [LA] and a second-order dependency on [BnOH].
authors.affiliation: Department of Chemistry, National Chung Hsing University, Taichung 402, Taiwan, ROC.
authors.forename: Mon-Wei
authors.initials: MW
authors.lastname: Hsiao
authors.forename: Chu-Chieh
authors.initials: CC
authors.lastname: Lin
mesh_terms: D019905:Benzyl Alcohol / Q000737:chemistry; D002118:Calcium / Q000737:chemistry*; D002384:Catalysis; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004146:Dioxanes / Q000737:chemistry*; D007700:Kinetics; D008968:Molecular Conformation; D058105:Polymerization
chemical_list: D056831:Coordination Complexes; D004146:Dioxanes; C091880:dilactide; D019905:Benzyl Alcohol; D002118:Calcium