LAUSR

By condensing 1,1-dicarboxy-2-vinylcyclopropane with l-alanine methyl ester, a new chiral vinylcyclopropane derivative bearing two amide moieties 1 was synthesized. The vinylcyclopropane thus prepared was separated into two epimers, namely, RSS-1 and SSS-1. Both the epimers and an epimeric mixture underwent radical ring-opening polymerization (RROP), where the number-average molecular weights (Mns) of the polymers depended on the configuration of 1; i.e., the RROP of SSS-1 gave the corresponding polymer, of which Mn was higher than the polymer obtained by the RROP of RSS-1. This difference in polymerization behaviors was correlated successfully with the difference in manners of intermolecular and intramolecular hydrogen bonds between the two epimers, which were clarified by the polymerization of SSS-1 was assisted by intermolecular hydrogen bonds. Besides the RROP in solution, the RROP of SSS-1 in its solid state was investigated to find that it afforded the corresponding polymer highly efficiently.