Aluminum Salen Complexes Modified with Unsaturated Alcohol: Synthesis, Characterization, and Their Activity towards Ring-Opening Polymerization of ε-Caprolactone and ,-Lactide.

A highly efficient one-step approach to the macromonomer synthesis using modified aluminum complexes as catalysts of ring-opening polymerization (ROP) of ε-caprolactone and ,-lactide was developed. The syntheses, structures, and catalytic activities of a wide range of aluminum salen complexes, , functionalized with unsaturated alcohol (HO(CH)OCH=CH) are reported. X-Ray diffraction studies revealed a tetragonal pyramidal structure for . Among the complexes -, the highest activity in bulk ROP of ε-caprolactone and ,-lactide was displayed by , affording polyesters with controlled molecular weights at low monomer to initiator ratios ( up to 15,000 g mol), relatively high polydispersities (Ð~1.8) and high number-average functionalities ( up to 85%).