Asymmetric Polymerizations of (S)-N-Maleoyl-L-Phenylalanine Derivatives Bearing Allyl Groups and Chiral Recognition Abilities of Their Polymers

Abstract

Novel N-substituted maleimides bearing an L-phenylalanine allyl ester or allyl amide as an N-substituent: allyl ester ((S)-APAMI), allyl amide ((S)-AAPAMI) and diallyl amide ((S)-DAAPAMI) were synthesized from maleic anhydride, L-phenylalanine, allyl alcohol, allyl amine and diallyl amine. Asymmetric polymerizations of maleimide monomers were performed with organometal/chiral ligands to obtain optically active polymers. The polymers obtained by anionic polymerizations showed specific optical rotations of [α]₄₃₅²⁵=-91.8°~-352.8°. The specific optical rotations and CD spectral patterns of the polymers were different from those of the model compounds for the polymers. These differences indicated that asymmetric induction took place on the main chain in all polymerization systems. The chemical-bonded-type chiral stationary phase for HPLC prepared from the polymer resolved some racemates.