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.