Nitrido Osmium Compounds

Orthotelluric acid, 3 145,147 Osmium compounds, nitrido, 6 204 Osmium (IV) oxide, formation of black, by ammonium hexa-bromoosmate(IV), 5 206 Osmium(VIII) oxide, precautions in using, 5 205... 

The electrochemical properties of a number of isostructural rhe-nium(V) oxo, rhenium(V) imido, osmium(VI) nitrido, of formula [M(E)(X)(Y)(Tp )] (Tp = Tp or Tp, E = O, N-tolyl, N X, Y = hydrocarbyl, halide, triflate), have been described. The reactivity of these complexes as inner-sphere oxidants does not correlate with their peak reduction potentials, whereas the ease of the oxidation of these compounds well parallels their reactivity as oxidants.206... 

There is a vigorously expanding chemistry of compounds of ruthenium and osmium in high oxidation states [3, 4, 11, 12], particularly of dioxo and nitrido compounds, though recently some striking developments have taken place in imide chemistry. 

Os (Tp)(OTf)(Cl)2] can abstract a nitrogen atom from MeCN upon heating to give the osmium nitrido compound [Os (N)(Tp)(Cl)2] (Equation (75)). The suggested mechanism is hydrolysis at Os followed by redox disproportionation to Os and Os ... 

Nitric anhydride, 3 78 Nitric oxide [see Nitrogen (II) oxide] Nitrido compounds with osmium, 6 204... 

Osmium nitrido species may be luminescent and have other photophysical and chemical properties and Os 1 compounds such as [0s(N)(bipy)Cl2(H20)]+ and [Os(N)(NH3)4]3+ have been studied in some detail.116 Interaction of [Os(N)C14] and... 

While inorganic complexes of osmium in oxidation states +4 through +8 have been known for many years, the study of high-valent alkyl and aryl complexes of osmium is much more recent. The organometallic complexes include homoleptic see Homoleptic Compound) alkyls and aryls, oxo alkyls and aryls, nitrido/imido alkyls and aryls, and cyclopentadienyl see Cyclopentadienyl) alkyls and aryls. The majority of these are complexes of osmium(VI). 

The chemistry of ruthenium and osmium bears little resemblance to that of iron except in compounds such as sulfideror phosphides, and in complexes with ligands such as CO, PR3, or A5-C5H5. The higher oxidation states, VI and VIII, are much more readily obtained than for iron and there is an extensive and important chemistry of the tetraoxides, M04, oxohalides and oxo anions. There are analogies between the chemistries of Ru, Os and Re especially in oxo, nitrogen and nitrido compounds. 

A. Neuhaus, A. Veldkamp, and G. Frenking, Inorg. Chem., 33, 5278 (1994). Oxo and Nitrido Complexes of Molybdenum, Tungsten, Rhenium and Osmium. A Theoretical Study. Theoretical Studies of Inorganic Compounds. IV. 

Haber has already demonstrated that Os is also a promising heterogeneous catalyst for NH3 synthesis, but the number of molecular Os—N2 or Os— N2H4 complexes is rather limited. This is caused by the fact that osmium forms relatively labile N2 compounds, which are usually not a result of direct N2 activation, but formed (a) by intermolecular N-"N coupling between two osmium nitridos, (b) by (thermal/photochemical) activation of... 

As befits current interest, the largest number of reviews centre on metal carbonyl cluster compounds. General topics covered included electron transfer reactions, ligand and cluster transformations, and the chemistry of metal clusters containing nitrosyl and nitrido ligands.More specific topics reviewed include sulphi do-osmium carbonyl cluster compounds,and homonuclear platinum clusters.The preparations of [Nb(C0)6] [M2(CO)io(m-H)]" (M = Cr or W), Mn2(C0)aX2 and Re C0)sX (X = Cl, Br or I) are described in Volume 23 of Inorganic Syntheses. ... 

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