title: Experimental and theoretical studies on arene-bridged metal-metal-bonded dimolybdenum complexes.
abstract: The bis(hydride) dimolybdenum complex, [Mo2(H)2{HC(N-2,6-iPr2C6H3)2}2(thf)2], 2, which possesses a quadruply bonded Mo2(II) core, undergoes light-induced (365 nm) reductive elimination of H2 and arene coordination in benzene and toluene solutions, with formation of the Mo(I)2 complexes [Mo2{HC(N-2,6-iPr2C6H3)2}2(arene)], 3⋅C6H6 and 3⋅C6H5Me, respectively. The analogous C6H5OMe, p-C6H4Me2, C6H5F, and p-C6H4F2 derivatives have also been prepared by thermal or photochemical methods, which nevertheless employ different Mo2 complex precursors. X-ray crystallography and solution NMR studies demonstrate that the molecule of the arene bridges the molybdenum atoms of the Mo(I)2 core, coordinating to each in an η(2) fashion. In solution, the arene rotates fast on the NMR timescale around the Mo2-arene axis. For the substituted aromatic hydrocarbons, the NMR data are consistent with the existence of a major rotamer in which the metal atoms are coordinated to the more electron-rich C-C bonds.
authors.affiliation: Instituto de Investigaciones Químicas, Departamento de Química Inorgánica Universidad de Sevilla-Consejo Superior de Investigaciones Científicas, Avenida Américo Vespucio 49, 41092 Sevilla (Spain), Fax: (+34) 954460565.
authors.forename: Mario
authors.initials: M
authors.lastname: Carrasco
authors.forename: Natalia
authors.initials: N
authors.lastname: Curado
authors.forename: Eleuterio
authors.initials: E
authors.lastname: Álvarez
authors.forename: Celia
authors.initials: C
authors.lastname: Maya
authors.forename: Riccardo
authors.initials: R
authors.lastname: Peloso
authors.forename: Manuel L
authors.initials: ML
authors.lastname: Poveda
authors.forename: Amor
authors.initials: A
authors.lastname: Rodríguez
authors.forename: Eliseo
authors.initials: E
authors.lastname: Ruiz
authors.forename: Santiago
authors.initials: S
authors.lastname: Álvarez
authors.forename: Ernesto
authors.initials: E
authors.lastname: Carmona
keywords: NMR spectroscopy; arenes; density functional calculations; molybdenum; multiple bonds