Synthesis, characterization and cyclic voltammetric studies of ruthenium oximates

Abstract

of Summary Using 1,2-naphthoquinone-1-oxime (HL) as the principal ligand, four mixed-ligand ruthenium oximate complexes -namely [Ru(bipy)2(L)]C104, [Ru(pap)a(L)]-C10 4, [Ru(bipy)(L)2 ] and [Ru(PPh3)2(L)2 ], where bipy = 2,2'-bipyridine and pap = 2-(phenylazo)pyridinehave been synthesized and characterized. In all these complexes, Ru exists in the + 2 state. They are diamagnetic and, in solution, show several intense metal-toligand charge transfer (MLCT) transitions in the vis. region. In MeCN solution, all four complexes show a reversible Run-Ru m oxidation on the positive side of a standard calomel electrode (s.c.e.), the potential of which varies with the compositions of the complexes. Reductions of the coordinated co-ligands (bipy or pap) are also observed.

Tris 1-Nitroso-2-naphtholate Complex of Ruthenium(II): An Efficient Building Unit for Polynuclear Complexes

“…The first oxidation, observed at 0.50 V, is reversible and is assigned to the Ru II −Ru III oxidation . It may be mentioned here that the appearance of Ru II −Ru III oxidation in the [Ru II (L) 3 ] - complex near the observed potential was predicted in our earlier report on some mixed-ligand 1-nitroso-2-naphtholate complexes of ruthenium . The second oxidation, observed at 1.35 V, is irreversible and is tentatively assigned to the Ru III −Ru IV oxidation.…”

Synthesis, Characterisation and Electrochemical Behaviour of Rhodium(III) Complexes Containing 1,2-Naphthoquinone-2-oxime and Formation of Imine Complexes through N−O Bond Cleavage

“…In ruthenium 1,2‐naphthoquinone‐1‐oxime complexes, the MLCT from ruthenium(II) to the ligand occurs with comparatively low energy 10. The existence and the number of this ligand in 2,2‐bipyridine‐containing ruthenium complexes influence the electrochemical property of the metal centre 11. Metal complexes containing 1,2‐naphthoquinone‐monooximes are of interest as they are widely used for analytical purposes12,13 and are potentially useful for the preparation of a wide variety of organic compounds 14−17.…”