rac-Lactide Polymerization with Copper(II) Complexes

نویسندگان

  • Pargol Daneshmand
  • Solène Fortun
  • Todd J. J. Whitehorne
  • Frank Schaper
چکیده

Stereocontrolled coordination-insertion polymerization of rac-lactide remains a catalytic challenge despite the large number of studies and the successful marketing of polylactide as a disposable plastic. Although a number successful catalysts have been proposed, a system re-uniting high stereoselectivity with high activity and chemical robustness remains absent. We have been recently concentrating on transition metal catalysts with partially filled d-shells, which have been surprisingly neglected compared to d 10 or d 0 -systems. In particular, Cu(II)-based catalysts offered surprising reactivity patterns. Diketiminate copper(II) systems proved to be among the most active lactide-polymerization catalysts, without evidence of secondary reactions or chain-release even under starved-monomer conditions. [1-3]

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تاریخ انتشار 2016