New titanium and zirconium initiators for the production of polylactide

Two new group 4 initiators based on N,N'-Bis(2-hydroxybenzyl)ethylenediamine have been prepared and fully characterised via multi-nuclear NMR spectroscopy and single crystal X-ray diffraction studies. The complexes have been tested for the production of polylactide. The phenolate ligand complexes to Ti(IV) to generate the beta-cis isomer in the solid-state. Whereas for Zr(IV) the isolated species (regardless of stoichiometery) is a diligated complex. (C) 2009 Elsevier Ltd. All rights reserved.