Aluminium complexes of salanol ligands: coordination chemistry and stereoselective lactide polymerization.

The tetradentate dianionic {ONNO}-type salanol ligands featuring phenolate and alcoholate arms and a chiral-bipyrrolidine core are introduced. The diastereoselectively-formed {ONNO}-Al-OBn complexes catalyze the ring-opening polymerization of rac-lactide and meso-lactide by either the dual stereocontrol or the chain-end stereocontrol mechanisms to give PLAs of all possible tacticities.