10.1021/ol017113n
The study focuses on the highly selective asymmetric polymerization of 1,2-diisocyanobenzene to form enantiopure helical poly(quinoxaline-2,3-diyl) using a novel organopalladium initiator that contains the (4S,5S)-N-acyl-4,5-dihydro-4,5-diphenyl-1H-imidazol-2-yl group. This initiator serves as a polymer-end screw-sense-determinant, which is crucial for creating structurally well-defined helical polymers with a single screw-sense. The polymers, due to their helical structures, have potential applications as functional materials. The researchers explored alternative chiral groups that are easily accessible and provide efficient chiral environments, using chiral phenylpalladium initiators substituted with optically active o-substituents such as aminocarbonyl, oxazoline, and imidazoline groups derived from chiral amine precursors. The study aimed to develop a method for synthesizing polymers with stable single-handed screw-sense that do not undergo significant racemization, with the goal of achieving high screw-sense selectivity in the polymerization process.