Well-defined polymers with acetal side chains as reactive scaffolds synthesized by atom transfer radical polymerization

The synthesis of a polymer with acetal functionalized side chains, deprotection to aldehydes, and conjugation of aminooxy-modified molecules is reported. Poly(3,3'-diethoxypropyl methacrylate) (PDEPMA) was prepared by atom transfer radical polymerization (ATRP). Kinetic investigation of the ATRP of DEPMA from ethyl 2-bromoisobutyrate in methanol with copper (1) bromide and 2,2'-bipyridine (BIPY) at ambient temperature revealed a controlled polymerization. Altering the initial monomer to initiator ratios resulted in 75-93% conversion to polymers with different molecular weights and narrow molecular weight distributions (PDIs < 1.3). Reactive aldehyde groups were produced by hydrolysis of the acetals in dilute acid. Aminooxy-functionalized oligo(ethylene glycol) and O-(carboxymethyl)hydroxylamine were conjugated to the side chains via oxime linkages. (c) 2006 Wiley Periodicals, Inc.