Sequential Post-Polymerization Modification of Aldehyde Polymers to Ketone and Oxime Polymers

A new sequential post-polymerization modification route has been developed for the synthesis of multifunctional polymers from a simple aldehyde polymer. In the first modification step, a template polymer derived from the radical polymerization of 4-vinyl benzaldehyde undergoes Rh-catalyzed hydroacylation with alkenes to furnish a group of ketone polymers. In the second modification step, Schiff base formation with alkoxy ammonium salts introduces a second group—an oxime functionality. Both the steps are highly efficient, introducing evenly distributed dual functionalities at the same position.