10.1021/om950943i.s001 Francisco Amor Francisco Amor Pilar Gómez-Sal Pilar Gómez-Sal Ernesto de Jesús Ernesto de Jesús Avelino Martín Avelino Martín Ana I. Pérez Ana I. Pérez Pascual Royo Pascual Royo Amelio Vázquez de Miguel Amelio Vázquez de Miguel Dimetallic Imido Complexes of Molybdenum and Tungsten with Bridged Bis(η<sup>5</sup>-cyclopentadienyl) Ligands. Molecular Structure of [(MoO)<sub>2</sub>(μ-N<i><sup>t</sup></i>Bu)<sub>2</sub>{μ-(η<sup>5</sup>-C<sub>5</sub>H<sub>4</sub>)<sub>2</sub>SiMe<sub>2</sub>}] American Chemical Society 1996 PCl 5 Complexes 4 Cp analogues sodium amalgam THF solution trans isomers Cp 2 Cp complexes 2 SiMe 2 Molecular Structure Cp 2 Cp system C 5 H 3 C 5 H 4 metal fragments CH 3 Cp 1 Cp SiMe 2 oxo dimetallic complexes H 2 N t Bu Cp 2 Cp Dimetallic Imido Complexes 1996-04-16 00:00:00 Journal contribution https://acs.figshare.com/articles/journal_contribution/Dimetallic_Imido_Complexes_of_Molybdenum_and_Tungsten_with_Bridged_Bis_sup_5_sup_-cyclopentadienyl_Ligands_Molecular_Structure_of_MoO_sub_2_sub_-N_i_sup_t_sup_i_Bu_sub_2_sub_-_sup_5_sup_-C_sub_5_sub_H_sub_4_sub_sub_2_sub_SiMe_sub_2_sub_/3776979 New imido and oxo dimetallic complexes of Mo and W with the monobridged or dibridged bis(cyclopentadienyl) ligands Cp<sup>1</sup>Cp or Cp<sup>2</sup>Cp [Cp<sup>1</sup>Cp = (η<sup>5</sup>-C<sub>5</sub>H<sub>4</sub>)<sub>2</sub>SiMe<sub>2</sub>, Cp<sup>2</sup>Cp = (η<sup>5</sup>-C<sub>5</sub>H<sub>3</sub>)<sub>2</sub>(SiMe<sub>2</sub>)<sub>2</sub>] have been synthesized. The Cp<sup>2</sup>Cp complexes have been obtained as both <i>cis</i> and <i>trans</i> isomers which differ in the stereodisposition of the two metal fragments with respect to the Cp<sup>2</sup>Cp system, the stereochemistry being unchanged in all the reactions described. Addition of H<sub>2</sub>N<i><sup>t</sup></i>Bu to [(MCl<sub>4</sub>)<sub>2</sub>(μ-Cp<i><sup>n</sup></i>Cp)] (M = Mo, <i>n</i> = 1, <b>2a</b>; <i>n</i> = 2, <b>2b</b>; M = W, <i>n</i> = 2, <b>2c</b>) affords the imido M(V) complexes [{M(N<i><sup>t</sup></i>Bu)Cl<sub>2</sub>}<sub>2</sub>(μ-Cp<i><sup>n</sup></i>Cp)] (<b>4a−c</b>). Complexes <b>4a,c</b> are oxidized by PCl<sub>5</sub> to give [{M(N<i><sup>t</sup></i>Bu)Cl<sub>3</sub>}<sub>2</sub>(μ-Cp<i><sup>n</sup></i>Cp)] (<b>5a,c</b>). Both <b>4a</b> and <b>5a</b> afford [{MoCl(μ-N<i><sup>t</sup></i>Bu)}<sub>2</sub>(μ-Cp<sup>1</sup>Cp)] (<b>6</b>) by reduction with sodium amalgam. The differences found between this reaction and the related reductions of the mononuclear Cp analogues are discussed. Reaction of <b>6</b> with HgO affords the oxo complex [{MoO(μ-N<i><sup>t</sup></i>Bu)}<sub>2</sub>(μ-Cp<sup>1</sup>Cp)] (<b>7</b>). [(MoOCl)<sub>2</sub>(μ-O)(μ-Cp<sup>2</sup>Cp)] (<b>3</b>) is obtained by reaction of [{Mo(CO)<sub>3</sub>Cl}<sub>2</sub>(μ-Cp<sup>2</sup>Cp)] with CH<sub>3</sub>NO<sub>2</sub> or bubbling air through a THF solution of <i>cis</i>-[(MoCl<sub>4</sub>)<sub>2</sub>(μ-Cp<sup>2</sup>Cp)]. The molecular structure of <b>7</b> has been determined by a single-crystal X-ray analysis.