Ring-opening polymerization of l-lactide catalyzed by a biocompatible calcium complex

A novel calcium complex, [(DAIP)2Ca]2 (where DAIP-H = 2-[(2-dimethylamino-ethylimino)methyl]phenol), is prepared in a one flask reaction by condensation of Ca(OMe)2 with DAIP-H in toluene/THF. Experimental results show that in the presence of various alcohols, [(DAIP)2Ca]2 efficiently initiates the ring-opening polymerization of l-lactide in a controlled fashion, yielding polymers with expectative molecular weight and low polydispersity indexes. Furthermore, kinetic studies show a first-order dependency on both [LA] and [BnOH].