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Copper(II) complexes with imino phenoxide ligands: synthesis, characterization, and their application as catalysts for the ring-opening polymerization of rac-lactide.

ABSTRACT: Four new copper complexes based on bidentate imino phenoxide ligands were synthesized and characterized by IR, UV-Vis spectroscopy, ESI mass spectrometry, single crystal X-ray diffraction, and electrochemistry. The crystal structures revealed that the copper(II) atoms are surrounded by phenolate oxygen and imine nitrogen atoms of two ligands in a distorted square-planar geometry. The existence of ligand-centered, as well as Cu(II)-centered quasi-reversible and reversible redox reactions are observed in the cyclic voltammetry experiments of all the complexes. All complexes are able to catalyze the ring-opening polymerization of rac-lactide yielding polymers with moderate molecular weights and moderately broad molecular weight distributions.

SUBMITTER: Mandal M

PROVIDER: S-EPMC5063905 | biostudies-other | 2016

REPOSITORIES: biostudies-other

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Copper(II) complexes with imino phenoxide ligands: synthesis, characterization, and their application as catalysts for the ring-opening polymerization of rac-lactide.

Mandal Mrinmay M Oppelt Kerstin K List Manuela M Teasdale Ian I Chakraborty Debashis D Monkowius Uwe U

Monatshefte fur chemie 20160905 11

<h4>Abstract</h4>Four new copper complexes based on bidentate imino phenoxide ligands were synthesized and characterized by IR, UV-Vis spectroscopy, ESI mass spectrometry, single crystal X-ray diffraction, and electrochemistry. The crystal structures revealed that the copper(II) atoms are surrounded by phenolate oxygen and imine nitrogen atoms of two ligands in a distorted square-planar geometry. The existence of ligand-centered, as well as Cu(II)-centered quasi-reversible and reversible redox r ...[more]

PMID: 27795584

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Palladium complexes containing imino phenoxide ligands: synthesis, luminescence, and their use as catalysts for the ring-opening polymerization of rac-lactide.

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