Air-stable titanium alkoxide based metal-organic framework as an initiator for ring-opening polymerization of cyclic esters.

An air-stable titanium-organic framework, prepared from Ti(OiPr)4 and 1,4-butanediol, has been characterized via single-crystal X-ray diffraction, revealing a unique supramolecular structure. Its functionality as a highly active initiator for the ring-opening polymerization of cyclic esters is demonstrated. A discrete titanium trimer containing the related ligand (2R,3R)-2,3-butanediol has also been prepared, and it shows analogous activity as a polymerization initiator.