title: Isotactic rac-Lactide Polymerization with Copper Complexes: The Influence of Complex Nuclearity.
abstract: Diiminopyrrolide copper alkoxide complexes, LCuOR (OR(1)=N,N-dimethylamino ethoxide, OR(2)=2-pyridyl methoxide), are active for the polymerization of rac-lactide at ambient temperature in benzene to yield polymers with M(w)/M(n)=1.0-1.2. X-ray diffraction studies showed bridged dinuclear complexes in the solid state for both complexes. While LCuOR(1) provided only atactic polylactide, LCuOR(2) produced partially isotactic polylactide (P(m)=0.7). The difference in stereocontrol is attributed to a dinuclear active species for LCuOR(2) in contrast to a mononuclear species for LCuOR(1).
authors.affiliation: Centre in Green Chemistry and Catalysis, University of Montreal, Department of Chemistry, C. P. 6128 Succ. Centre-Ville, Montréal, QC, H3C 3J7 (Canada).
authors.forename: Solène
authors.initials: S
authors.lastname: Fortun
authors.affiliation: Centre in Green Chemistry and Catalysis, University of Montreal, Department of Chemistry, C. P. 6128 Succ. Centre-Ville, Montréal, QC, H3C 3J7 (Canada).
authors.forename: Pargol
authors.initials: P
authors.lastname: Daneshmand
authors.affiliation: Centre in Green Chemistry and Catalysis, University of Montreal, Department of Chemistry, C. P. 6128 Succ. Centre-Ville, Montréal, QC, H3C 3J7 (Canada). Frank.Schaper@umontreal.ca.
authors.forename: Frank
authors.initials: F
authors.lastname: Schaper
mesh_terms: D003300:Copper / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004146:Dioxanes / Q000737:chemistry*; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000737:chemistry*; D058105:Polymerization
chemical_list: D004146:Dioxanes; D009942:Organometallic Compounds; D003300:Copper; C091880:dilactide
keywords: N ligands; copper; homogeneous catalysis; lactide; ring-opening polymerization