Cobalt‐Mediated Switchable Catalysis for the One‐Pot Synthesis of Cyclic Polymers

A cobalt salen pentenoate complex [salen=( R , R )‐ N , N ′‐bis(3,5‐di‐tertbutylsalicylidene)‐1,2‐cyclohexanediamine] is rationally designed as the catalyst for the ring‐opening copolymerization (ROCOP) of epoxides/anhydrides/CO 2 . Via migratory insertion of carbon monoxide (CO) into the Co−O bonds, the ROCOP‐active species α‐alkene‐ω‐O‐Co III (salen) can be rapidly and quantitatively transformed into α‐alkene‐ω‐O 2 C‐Co III (salen) telechelic...