title: Mechanistic Insights into the Carbon Dioxide/Cyclohexene Oxide Copolymerization Reaction: Is One Metal Center Enough?
abstract: A detailed study on the mechanism for the alternating copolymerization of cyclohexene oxide (CHO) and CO2mediated by an [Al{amino-tri(phenolate)}]/NBu4I binary catalyst system was performed by using DFT-based methods. Four potential mechanisms (one monometallic and three bimetallic) were considered for the first propagation cycle of the CHO/CO2copolymerization. The obtained Gibbs free energies provided a rationale for the relative high activity of a non-covalent dimeric structure formed in situ and thus for the feasibility of a bimetallic mechanism to obtain polycarbonates quantitatively. Gibbs free energies also indicated that the alternating copolymerization was favored over the cyclic carbonate formation.
authors.affiliation: Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain.
authors.forename: Joan
authors.initials: J
authors.lastname: González-Fabra
authors.affiliation: Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Castro-Gómez
authors.affiliation: Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain.|Catalan Institute of Research and Advanced Studies (ICREA), Pg. Lluís Companys 23, 08010, Barcelona, Spain.
authors.forename: Arjan W
authors.identifier: 0000-0002-7402-4764
authors.initials: AW
authors.lastname: Kleij
authors.affiliation: Institute of Chemical Research of Catalonia (ICIQ), The Barcelona Institute of Science and Technology, Av. Països Catalans 16, 43007, Tarragona, Spain.|Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, Marcellí Domingo s/n, 43007, Tarragona, Spain.
authors.forename: Carles
authors.identifier: 0000-0001-9581-2922
authors.initials: C
authors.lastname: Bo
mesh_terms: D000535:Aluminum / Q000737:chemistry*; D002245:Carbon Dioxide / Q000737:chemistry*; D002384:Catalysis; D053138:Cyclohexenes / Q000737:chemistry*; D004852:Epoxy Compounds / Q000737:chemistry; D008958:Models, Molecular; D008968:Molecular Conformation; D009942:Organometallic Compounds / Q000737:chemistry; D058105:Polymerization; D011789:Quantum Theory; D013816:Thermodynamics
chemical_list: D053138:Cyclohexenes; D004852:Epoxy Compounds; D009942:Organometallic Compounds; D002245:Carbon Dioxide; C007193:cyclohexene oxide; D000535:Aluminum
keywords: DFT analysis; carbon dioxide; copolymerization; cyclohexene oxide; homogeneous catalysis