High Oxidation State Organocobalt Complexes: Synthesis and Characterization of Dihydridodisilyl Cobalt(V) Species

Reactions of Hydrosilanes with Transition Metal Complexes and Characterization of the Products

“…The Co V complex Cp*(H) 2 Co(SiPh 2 H) 2 (2-52a) was crystallographically characterized, but the hydrides could not be located. 103 The DFT calculations (B3LYP) gave a Co-Si distance of 2.29 Å compared to the experimentally determined 2.26 Å as well as a pseudo-square-pyramidal structure. From the calculated H · · · H distance of 2.28 Å and H · · · Si distances of 2.24 and 2.25 Å, the authors favored a complete oxidative addition of both equivalents of Ph 2 SiH 2 to the starting materials, Cp*Co(η 2 -H 2 CdCHR) (R ) H, SiMe 3 ).…”

“…56 58 Contains 4 independent molecules in cell. 103 complex, often formed from a hydrosilane, where the X-substituent is a functional group that may be removed in an abstraction reaction. The intramolecular base stabilization results either from a substituent on the silylene center that has a base tether, or is formed from OA of HSiMe 2 SiMe 2 X (X ) OMe, NR 2 ) to a transition metal complex followed by migration of SiMe 2 X to the metal and coordination of X to the silylene center.…”

“…506 other, some residual interaction may be present (as in SISHA), although there were no silicon satellites observed for the Co-H signal. 103 In the mono(silyl)-and bis(silyl)-o-carboranes that are chelated to a Cp*(H) 2 Ir fragment in 3-228, 3-229, and the related complex formed from o-(HMe 2 Si) 2 C 6 H 4 , 3-231, the basic structure was that of a four-legged piano-stool geometry with the Cp* ligand in an apical position. 172 The crystal structures of 3-228 and 3-231 were reported.…”

Multinuclear palladium compounds containing palladium centers ligated by five silicon atoms

“…Electrochemical formation of PdO 3 is also suggested (9). It is also known that more electropositive ligands such as hydride and silyl ligands can form stable transition-metal compounds with high formal oxidation states such as K 2 Re VII H 9 , (Me 5 C 5 )Ir V H 4 , and (Me 5 C 5 )M V (H) 2 (SiEt 3 ) 2 (M ϭ Co, Rh, Ir) (10)(11)(12)(13)(14).…”

The broad diversity of CpCo(I) complexes

“…In the wake of discovering evidence for intermediates of the Co(III)-catalyzed olefin hydrosilylation, the complexes of the type [Cp*Co{P(OMe) 3 }(CH 2 = CHSiR 3 )] (R = Me, Et, 72 and 73) were synthesized and studied via NMR (Brookhart and Grant 1993). The formation of Co(V) intermediates was also discussed and the corresponding complexes were synthesized and characterized by X-ray (Brookhart et al 2000). Similar studies were done for an ethylene polymerization catalyst.…”