Osmium 2,2 : 6 ,2 -terpyridine

Like mthenium, amines coordinated to osmium in higher oxidation states such as Os(IV) ate readily deprotonated, as in [Os(en) (NHCH2CH2NH2)] [111614-75-6], This complex is subject to oxidative dehydrogenation to form an imine complex (105). An unusual Os(IV) hydride, [OsH2(en)2] [57345-94-5] has been isolated and characterized. The complexes of aromatic heterocycHc amines such as pyridine, bipytidine, phenanthroline, and terpyridine ate similar to those of mthenium. Examples include [Os(bipy )3 [23648-06-8], [Os(bipy)2acac] [47691-08-7],... 

Vectorial transfer of electronic energy in rod-like ruthenium-osmium complexes with bis-2,2, 2"-terpyridine ligands 97CC333. 

Barigelletti F et al (1993) Luminescence properties of rigid rod-like binuclear ruthenium(II)-osmium(II) terpyridine complexes - electronic interaction through phenyl bridges. JCS Chem Commun 942-944... 

Figure 4. Ruthenium and osmium hetero-bi- and trinuclear complexes with bis(terpyridine) ligands bridged by one and two phenylene groups (98).

OSF9N5O10S3C28H31 2H2O, Osmium(III), aqua(2,2 -bipyridine-iV,N )(2,2 6, 2"-terpyridine-N,N, N")-, tris(trifluoro-methanesulfonate), dihydrate, 24 304 0sF9N60,S3C3H,8, Osmium(III), hexaam-mine-, tris(trifluoromethanesulfonate), 24 273... 

Sauvage, J. P. Collin, J. P. Chambron, J. C. Guillerez, S. Coudret, C. Balzani, V. Barigelletti, F. Decola, L. Flamigni, L. Ruthenium(II) and osmium(II) bis(terpyridine) complexes in covalently linked multicomponent systems - synthesis, electrochemical behavior, absorption spectra, and photochemical and photophysical properties. Chem. Rev. 1994, 94, 993-1019. 

The (2,2 -bipyridine-A(,A( )(2,2 6 2"-terpyridine-A(,yV, yV"),(bpy)(trpy) complexes of ruthenium and osmium, like the bis(2,2 -bipyridine-A(,N ) series, were first studied by Dwyer and coworkers " and are interesting because more than one oxidation state is substitution inert. More recently, these (bpy)(trpy) species have generated interest because the M(IV) oxo complexes are useful oxidants of organic molecules. " The (bpy)(trpy) series of complexes have also proved useful in the study of the redox chemistry of coordinated ligands. The (bpy)(trpy) and bis(bpy) complexes containing the coordinated trifluoromethanesulfonato (triflato) ligands are useful precursors to a variety of complexes. The syntheses of these species and the aqua complexes derived from them are reported here. 

The complex ion [Ru(bpy)(trpy)Cl] was first prepared as the perchlorate salt by the reaction of Ru(bpy)Cl4 with trpy in 25% aqueous ethanol, and more recently in 75% aqueous ethanol. It has also been prepared from Ru(CO)2(bpy)Cl2, trpy, and trimethylamine oxide in 2-methoxyethanol. A method in which the readily prepared RuftrpylClj complex is used as an intermediate is more convenient, and it is this new method that is described here. (2,2 -Bipyridine-A(,A( )chloro(2,2 6, 2"-terpyridine-Al,Al, N")osmium(II) chloride has been reported and is prepared from Os(bpy)Cl4" and trpy in ethylene glycol. (2,2 -Bipyridine-N,Al )chloro 2,2 6, 2"-terpyridine-Al,N, yV")osmium(II) chloride may also be prepared by the reaction of Os(trpy)Cl3 with bpy in ethylene glycol. However, the insolubility of Os(trpy)Cl3 in this solvent makes the procedure used for the ruthenium analog less desirable, and the literature method has been used without major modification. Reaction of the chloro complexes With hot... 

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