Synthesis of mono- and tetra-nuclear β-pyridylenolate zinc complexes and their catalysis toward the ring-opening copolymerization of ε-caprolactone and lactide

The novel tetra-nuclear β-pyridylenolate zinc complex was used to prepare the homopolymers (PCL, PLLA), block copolymer (PCL-b-PLLA) and gradient copolymer (PLLA-grad-PCL) of ε-CL and l-LA with high activity.213