Stereoregulation in N‐carboxy anhydride polymerization

Abstract
Copolymerization of N‐carboxy‐γ‐benzyl‐D‐ and L‐glutamate anhydride was examined in N,N‐dimethylformamide with n‐hexylamine as initiator. Rate increase was observed in the initial stage of polymerization of monomers with 55% and 87% L composition. The occurrence of asymmetric selection of monomer antipode was confirmed by optical‐rotation measurement of the polymers in trifluoroacetic acid as well as by optical rotatory‐dispersion measurement. Observed asymmetric selection and rate increase were discussed in relation to stereoregularity and to helix content of the polymer.