Formation of Methane versus Benzene in the Reactions of (C5Me5)(2)Th(CH3)(2) with [CH3PPh3]X (X=Cl, Br, I) Yielding Thorium-Carbene or Thorium-Ylide Complexes

bibtex: ISI:000412189700021 bibtex\location:'POSTFACH 101161, 69451 WEINHEIM, GERMANY',publisher:'WILEY-V C H VERLAG GMBH',type:'Article',affiliation:'Walensky, JR (Reprint Author), Univ Missouri, Dept Chem, Columbia, MO 65211 USA. Maron, L (Reprint Author), Univ Toulouse, 135 Ave Rangueil, F-31077 Toulouse, France. Maron, L (Reprint Author), LPCNO, CNRS, INSA, UPS,UMR,UMR 5215, 135 Ave Rangueil, F-31077 Toulouse, France. Rungthanaphatsophon, Pokpong; Bathelier, Adrien; Barnes, Charles L.; Walensky, Justin R., Univ Missouri, Dept Chem, Columbia, MO 65211 USA. Bathelier, Adrien; Castro, Ludovic; Maron, Laurent, Univ Toulouse, 135 Ave Rangueil, F-31077 Toulouse, France. Bathelier, Adrien; Castro, Ludovic; Maron, Laurent, LPCNO, CNRS, INSA, UPS,UMR,UMR 5215, 135 Ave Rangueil, F-31077 Toulouse, France.','author-email':'laurent.maron@irsamc.ups-tlse.fr walenskyj@missouri.edu',da:'2018-12-05','doc-delivery-number':'FI7PR',eissn:'1521-3773','funding-acknowledgement':'U.S. Department of Energy, Office of Science, Early Career Research Program [DE-SC-0014174]; Humboldt Foundation; Chinese Academy of Science; CalMip','funding-text':'J.R.W. gratefully acknowledges support for this work from the U.S. Department of Energy, Office of Science, Early Career Research Program under Award Number DE-SC-0014174. L.M. is member of the Instiut Universitaire de France. The Humboldt Foundation, the Chinese Academy of Science and CalMip is acknowledged for either financial support or computing time.','journal-iso':'Angew. Chem.-Int. Edit.','keywords-plus':'CARBON MULTIPLE BOND; MOLECULAR-STRUCTURE; METALLA-ALLENES; URANIUM COMPLEX; TRANS-INFLUENCE; U-IV=C; REACTIVITY; LIGAND; CHEMISTRY; PH2PNSIME3','number-of-cited-references':'42',oa:'Bronze','orcid-numbers':'Walensky, Justin/0000-0003-0221-2675','research-areas':'Chemistry','times-cited':'5','unique-id':'ISI:000412189700021','usage-count-last-180-days':'0','usage-count-since-2013':'9','web-of-science-categories':'Chemistry, Multidisciplinary'\; International audience; The reaction of (C5Me5)(2)Th(CH3)(2) with the phosphonium salts [CH3PPh3]X (X=Cl, Br, I) was investigated. When X=Br and I, two equivalents of methane are liberated to afford (C5Me5)(2)Th[CHPPh3]X, rare terminal phosphorano-stabilized carbenes with thorium. These complexes feature the shortest thorium-carbon bonds (approximate to 2.30 angstrom) reported to date, and electronic structure calculations show some degree of multiple bonding. However, when X = Cl, only one equivalent of methane is lost with concomitant formation of benzene from an unstable phosphorus(V) intermediate, yielding (C5Me5)(2)Th[kappa(2)-(C,C')-(CH2)(CH2)PPh2]Cl. Density functional theory (DFT) investigations of the reaction energy profiles for [CH3PPh3]X, X = Cl and I showed that in the case of iodide, thermodynamics prevents the production of benzene and favors formation of the carbene.