Abstract: | A series of LZnX zinc/β‐ketoiminato complexes L = CH3C(OH)?C(CH2CH?CH2)C(CH3)?NAr ( L1 ), CH3C(OH)?C(CH2CH2CN)C(CH3)?NAr ( L2 ), CH3C(OH)?C(CH2C6H5)C(CH3)?NAr ( L3 ), or CH3C(OH)?CHC(CH3)?NAr ( L4 ); Ar = 2,6‐iPr2C6H3; and initiation group X = alcoholate or acetate (for L1 ) or alcoholate (for L2 – L4 )] were synthesized, and their activities toward the copolymerization of carbon dioxide with cyclohexene oxide were determined. The 3‐position substituents on the β‐ketoiminato ligand backbone of the zinc/β‐ketoiminato complexes played an important role not only in the catalytic activity but also in the intrinsic viscosity, chemical composition, and refined microstructure of the resultant copolymers. The order of the catalytic activity of L1 ZnX with different initiation groups (X = OMe, OiPr, or OAc) was L1 Zn (OiPr) > L1 Zn (OMe) > L1 Zn (OAc), being the opposite of the order of the leaving ability of the initiation groups. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6243–6251, 2006 |