Solid Phase Synthesis of beta-Peptoids: N-Substituted beta-Aminopropionic Acid Oligomers.

A solid-phase organic synthesis method has been developed for the preparation of N-substituted-beta-aminopropionic acid oligomers or beta-peptoids 1. Treatment of polymer-bound 4-(benzyloxy)benzyl acrylate 2 with primary amines afforded N-substituted beta-alanines 3. Polymer loadings and product conversions were determined by direct cleavage of resin-bound materials and measurement by (1)H NMR with an internal standard.