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Cationic tetranuclear macrocyclic CaCo₃ complexes as highly active catalysts for alternating copolymerization of propylene oxide and carbon dioxide.

ABSTRACT: We found that a cationic hetero tetranuclear complex including a calcium and three cobalts exhibited high catalytic activity toward alternating copolymerization of propylene oxide (PO) and carbon dioxide (CO₂). The tertiary anilinium salt [PhNMe₂H][B(C₆F₅)₄] was the best additive to generate the cationic species while maintaining polymer selectivity and carbonate linkage, even under 1.0 MPa CO₂. Density functional theory calculations clarified that the reaction pathway mediated by the cationic complex is more favorable than that mediated by the neutral complex by 1.0 kcal mol^-1. We further found that the flexible ligand exchange between Ca and Co ions is important for the alternating copolymerization to proceed smoothly.

SUBMITTER: Nagae H

PROVIDER: S-EPMC10411860 | biostudies-literature | 2023 Aug

REPOSITORIES: biostudies-literature

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Cationic tetranuclear macrocyclic CaCo3 complexes as highly active catalysts for alternating copolymerization of propylene oxide and carbon dioxide.

Nagae Haruki H Matsushiro Saki S Okuda Jun J Mashima Kazushi K

Chemical science 20230712 31

We found that a cationic hetero tetranuclear complex including a calcium and three cobalts exhibited high catalytic activity toward alternating copolymerization of propylene oxide (PO) and carbon dioxide (CO2). The tertiary anilinium salt [PhNMe2H][B(C6F5)4] was the best additive to generate the cationic species while maintaining polymer selectivity and carbonate linkage, even under 1.0 MPa CO2. Density functional theory calculati ...[more]

PMID: 37564411

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