title: Concomitant Carboxylate and Oxalate Formation From the Activation of CO2by a Thorium(III) Complex.
abstract: Improving our comprehension of diverse CO2activation pathways is of vital importance for the widespread future utilization of this abundant greenhouse gas. CO2activation by uranium(III) complexes is now relatively well understood, with oxo/carbonate formation predominating as CO2is readily reduced to CO, but isolated thorium(III) CO2activation is unprecedented. We show that the thorium(III) complex, [Th(Cp'')3] (1, Cp''={C5H3(SiMe3)2-1,3}), reacts with CO2to give the mixed oxalate-carboxylate thorium(IV) complex [{Th(Cp'')2[κ2-O2C{C5H3-3,3'-(SiMe3)2}]}2(μ-κ2:κ2-C2O4)] (3). The concomitant formation of oxalate and carboxylate is unique for CO2activation, as in previous examples either reduction or insertion is favored to yield a single product. Therefore, thorium(III) CO2activation can differ from better understood uranium(III) chemistry.
authors.affiliation: School of Chemistry, The University of Manchester, Manchester, M13 9PL, UK.
authors.forename: Alasdair
authors.initials: A
authors.lastname: Formanuik
authors.affiliation: School of Chemistry, The University of Manchester, Manchester, M13 9PL, UK.
authors.forename: Fabrizio
authors.identifier: http://orcid.org/0000-0002-1743-8338
authors.initials: F
authors.lastname: Ortu
authors.affiliation: Department of Chemistry and Biochemistry, School of Life Sciences, University of Sussex, Brighton, BN1 9QL, UK.
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Inman
authors.affiliation: Department of Chemistry, Lancaster University, Lancaster, LA1 4YB, UK.
authors.forename: Andrew
authors.identifier: http://orcid.org/0000-0002-2876-1202
authors.initials: A
authors.lastname: Kerridge
authors.affiliation: LPCNO, CNRA and INSA, Université Paul Sabatier, 135 Avenue de Rangeuil, Toulouse, 31077, France.
authors.forename: Ludovic
authors.initials: L
authors.lastname: Castro
authors.affiliation: LPCNO, CNRA and INSA, Université Paul Sabatier, 135 Avenue de Rangeuil, Toulouse, 31077, France.
authors.forename: Laurent
authors.identifier: http://orcid.org/0000-0003-2653-8557
authors.initials: L
authors.lastname: Maron
authors.affiliation: School of Chemistry, The University of Manchester, Manchester, M13 9PL, UK.
authors.forename: David P
authors.identifier: http://orcid.org/0000-0003-1575-7754
authors.initials: DP
authors.lastname: Mills
keywords: actinides; reduction; small molecule activation; subvalent compounds; thorium