Convenient Synthesis of 1 → 3 C-Branched Dendrons

Abstract
A facile, efficient synthesis of 1 --> 3 C-branched polyamide dendrons is described. Treatment of acryloyl chloride with 1 --> 3 C-branched amines, e.g., di-tert-butyl 4-[2-(tert-butoxycarbonyl)ethyl]-4-aminoheptanedioate, gave the corresponding acrylamides in high yields, which upon reaction with nitromethane generated the homologated nitroalkane-polyesters. Finally, nitroalkane alkylation with 2 equiv of the acrylamides, followed by nitro group reduction, afforded the desired amino-polyesters.