79151-48-7Relevant articles and documents
Synthesis, characterization and hydrolysis of osmium tetraphosphorus complexes
Caporali, Maria,Di Vaira, Massimo,Peruzzini, Maurizio,Costantini, Stefano Senior,Stoppioni, Piero,Zanobini, Fabrizio
, p. 152 - 158 (2010/04/01)
The reaction of [CpOs(PPh3)2Cl] (1) with one equivalent of white phosphorus in the presence of AgOTf (OTf = triflate, OSO2CF3) as chloride scavenger affords the stable metal complex [CpOs(PPh3)2
Osmium alkyl and silyl derivatives with cyclopentadienyl(phosphine) and pentamethylcyclopentadienyl(phosphine) ligand sets
Wanandi, Paulus W.,Tilley, T. Don
, p. 4299 - 4313 (2008/10/08)
The preparation and characterization of new osmium(II) and osmium(IV) silyl derivatives containing the cyclopentadienyl(phosphine) and pentamethylcyclopentadienyl(phosphine) ligand sets are described. The osmium silyl complexes are prepared by thermal reactions of hydrosilanes with osmium(II) alkyl complexes of the type Cp′(PR3)2OsCH2SiMe3 (Cp′ = Cp, R = Ph (4), Me (5); Cp′ = η5-C5Me5, R = Me (7)), which in turn are available via alkylation of the corresponding bromo complexes. The synthesis of alkyl derivatives of Cp(PR3)2Os (R = Ph, Me) requires the use of dialkylmagnesium reagents, while alkylation of the more electron-rich Cp*(PMe3)2Os system can be achieved using Grignard reagents. Additionally, reaction of Cp(PPh3)2OsBr with AgOTf (Tf = SO2CF3) affords the osmium(II) triflate complex Cp(PPh3)2OsOTf (2), which possesses a labile triflate group. The structure of complex 2 was determined by X-ray crystallography. Similar to their ruthenium analogs, the osmium-(II) alkyl complexes 4, 5, and 7 thermally activate arene C-H bonds. Reaction of 7 with HSiR2[S(p-Tol)] (R = S(p-Tol), Me) provides metallacycle complexes of the type Cp*(PMe3)-(H)Os[C6H3(S-Me)(G-S)SiR 2] (R = S(p-Tol) (11), Me (13)) via activation of both the Si-H and arene C-H bonds in the silanes. The X-ray structure of 13 is described. Alkyl complexes 4, 5, and 7 react with HSiR2Cl (R = Ph, Me) to give osmium(II) silyl and/or osmium(IV) bis(silyl) hydride species, depending on the reaction conditions and the strength of the Os-P bond. Reaction of 7 with HSiMeCl2 or HSiCl3 affords, exclusively, the osmium(II) silyl derivatives. Exchange reactions at silicon are used to synthesize Cp*(PMe3)2OsSiMe2OTf (24) and Cp*(PMe3)2OsSiMe[S(p-Tol)]2 (25) from the corresponding chloro(silyl) complexes Cp*(PMe3)2OsSiMe2Cl (17) and Cp*(PMe3)2OsSiMeCl2 (18). The solution behavior and solid-state structure of 24 indicate that the compound may be described as a base-stabilized silylene complex.
CYCLOPENTADIENYL-RUTHENIUM AND -OSMIUM COMPLEXES. VI. FORMATION AND PROPERTIES OF DIHYDRIDO(η-CYCLOPENTADIENYL)BIS(TRIPHENYLPHOSPHINE)OSMIUM(IV) CATION. REACTION OF HYDRIDO(η-CYCLOPENTADIENYL)BIS(TRIPHENYLPHOSPHINE)OSMIUM(II) AND DIHYDRIDO(η-CYCLOPENTADIENYL)BIS(TRIPHENYLPHOSPHINE)...
Wilczewski, Tadeusz
, p. 307 - 326 (2007/10/02)
Several new compounds of the type (1+) X(1-), where X = Cl, Br, I, I3, BPh4, p-toluenesulphonate, d(+)-campho-10-sulphonate, have been obtained in the form of ion pairs or salts.The above compounds form during oxidative addition by HX acids to CpOsH(PPh3)2.The reactions are complete after several seconds, with a quantitative yield.This is in contrast to the behaviour of CpRuH(PPh3)2, where covalent CpRuX(PPh3)2 forms.Reaction of CpOsH(PPh3)2 with DCl acid (excess) gives Cl, but no Cl is formed.Refluxing CpOsBr(PPh3)2, in ethylene glycol for instance, gives a (1+) cation as a result of the dehydrogenation of the glycol.Compounds of the type, X, in solutions of polar solvents (MeOH) or halogenated hydrocarbons (e.g.CH2X2) undergo transformation to CpOsX(PPh3)2 during the reductive elimination process.In this way novel CpOsI(PPh3)2 has been obtained.In the case of the reaction of a mixture of HX + X2 with CpOsH(PPh3)2, Br3 (for Br2) and I3 (for I2) have been obtained in the form of sparingly soluble ion pars with yields of about 90percent.
