Ruthenium complexes nitrides

A complex nanostructured catalyst for ammonia synthesis consists of ruthenium nanoclusters dispersed on a boron nitride support (Ru/BN) with barium added as a promoter (33). It was observed that the introduction of barium promoters results in an increase of the catalytic activity by 2—3 orders of magnitude. The multi-phase catalyst was first investigated by means of conventional HRTEM, but this technique did not succeed in identifying a barium-rich phase (34). It was even difficult to determine how the catalyst could be active, because the ruthenium clusters were encapsulated by layers of the boron nitride support. By HRTEM imaging of the catalyst during exposure to ammonia synthesis conditions, it was found that the... 

SiMe3, x = 1-2 R = Me, x = 1-3), have also been prepared from the reaction of HCl(g) with the alkyl complexes (286). Reaction with Au(PPh3)Cl results in the formation of [Ru(N)ClMe3] and Au(PPh3)Me from [Ru(N)Me4], in a manner analogous to that of the HC1 reaction (286). In contrast to the related osmium complexes, Lewis acid adducts of the ruthenium nitrides are thermally unstable. 

A new class of binuclear nitrido complexes of tetravalent osmium and ruthenium is described in which the metal atoms are symmetrically bridged by a nitride ligand to give a linear M-N—M unit They have the stoichiometries M2NX8(H20)2]3 and [M2N(NH3)8Y2]3+ (M = Os, Ru X = Cl, Br Y = Cl, Br, etc.). Studies are reported on their vibrational spectra, structures, and bonding. Preliminary studies are reported also on trinuclear complexes of osmium and iridium. Finally, the use of vibrational spectroscopy in the study of metal-nitrido and metal-oxo complexes is discussed briefly. 

Bridging nitride ligands have been found in several dinuclear ruthenium(iv) and osmium(rv) complexes,23 e.g.,... 

Ruthenium(VI) and Ruthenium (VI 11).—Following a preliminary report, full details have appeared of the preparation and properties of the new ruthenium(vi) terminal nitride complexes Cs2[Ru(N)X5] and R[Ru(N)X4] (X = Cl or Br R = Ph4As or Bu4N). The dipole transition moment has been calculated for the lowest energy ti 2e transition for RUO4, employing a... 

Nitride, ruthenium cluster complex, 26 287 Nitrido, ruthenium clusters, 26 286 Nitrogen, iridium(III) complex, 26 119 Nitrosyls, molybdenum, 26 132 tungsten, 26 133... 

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