Synthesis and Polymerization of Bicyclic Ketals: A Practical Route to High-Molecular Weight Polyketals

Polyketals are an important class of materials for drug delivery to sensitive tissues as they degrade in vivo to nonacidic species. We report the synthesis of high-molecular weight cyclic polyketals by the cationic ring-opening polymerization of bicyclic ketal monomers, which were prepared by the metal-catalyzed rearrangement of epoxy ketones. Three different cyclic polyketals with high molecular weights were synthesized using this protocol.