Discrete Cationic Complexes for Ring-Opening Polymerization Catalysis of Cyclic Esters and Epoxides

A review. Many discrete cationic complexes have been designed and exhibited increasingly impressive catalytic performances for the ROP of epoxides and cyclic esters. The current state-of-the-art suggests that major breakthroughs cannot be foreseen in the homopolymn. of epoxides, due to the nature of the assocd. mechanisms, and as a consequence, interest in the use of metal cations to polymerize epoxides has dwindled. It seems to the authors that in view of the activated monomer mechanism that is often assocd. with discrete metal cations, this is clearly an area where the use of rationally devised cationic complexes could bring original breakthroughs.