Synthesis of Optically Active Polystyrene Catalyzed by Monophosphine Pd Complexes

Cationic Pd-II monophosphine complexes derived from alpha- and beta-cyclodextrins (CDs) promote the homopolymerization of styrene under carbon monoxide pressure. Although reversible CO coordination takes place under catalytic conditions according to C-13 NMR studies with C-13-enriched CO, both complexes catalyze the formation of CO-free styrene polymers. These macromolecules display optical activity as a result of the presence of stereoregular sequences within the overall atactic polymer.