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 (I) 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. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 5004–5013, 2006 Well‐defined poly(3,3′‐diethoxypropyl methacrylate), (PDEPMA) was prepared by atom transfer radical polymerization (ATRP) using ethyl 2‐bromoisobutyrate and CuBr/2,2′‐bipyridine (BIPY) in methanol at 21 °C. Different molecular weights and narrow molecular weight distributions (PDIs < 1.3) were obtained. To demonstrate the suitability of using this polymer as a reactive scaffold, the polymer side chains were hydrolyzed to aldehydes. Aminooxy‐functionalized oligo(ethylene glycol) and O‐(carboxymethyl)hydroxylamine were conjugated to the side chains forming oxime linkages.