Highly Syndiotactic Coordination (Co)polymerization of para-Methylselenostyrene

Synthesis of selenium-containing syndiotactic polystyrene through coordination polymerization is difficult to achieve since selenium atoms usually poison the applied catalysts. Herein, we report the coordination polymerization of para-methylselenostyrene (pMSS) and its copolymerization with styrene (St) using pyridyl-methylene-fluorenyl-supported complexes [(Py–CH2–Flu)­Ln­(CH2SiMe3)2(THF) n (Ln = Y (1), n = 1; Ln = Sc (2), n = 0)]. Complex 1 was completely inert, while complex 2 was highly active and exhibited >99% syndioselectivity to yield poly­(pMSS) as the rare crystalline polymer-containing selenium atoms in side chains. In addition, the copolymerization of polar pMSS with nonpolar St under various pMSS-to-St ratios proceeded smoothly. The excellent syndiotacticity was maintained in the copolymerization, and the obtained copolymers have random sequence distributions confirmed by 13C NMR spectrum analysis and kinetics study. The optical performances of the copolymers with different incorporations of selenium were studied.