Synthetic and catalytic investigations of ruthenium(III) complexes with triphenylphosphine/triphenylarsine and tridentate Schiff base

Abstract

The synthesis and characterization of several hexa-coordinated ruthenium(III) complexes of the type [RuCl(PPh 3 ) 2 (L)] (L = dibasic tridentate ligand derived by the condensation of salicylaldehyde/ovanillin with o-aminophenol/o-aminothiophenol) are reported. IR, electronic, EPR spectral data and redox bahaviour of the complexes are discussed. An octahedral geometry has been tentatively proposed for all the complexes. The new complexes were found to be effective catalysts for the oxidation of benzyl alcohol and cyclohexanol to benzaldehyde and cyclohexanone respectively using N-methylmorpholine-N-oxide as a co-oxidant.

Synthesis, spectral characterization, electrochemistry and catalytic activities of Cu(II) complexes of bifunctional tridentate Schiff bases containing ONO donors

“…[5] Among these, catalytic oxidation of alcohols to carbonyl compounds is a pivotal reaction due to their utility in fine chemical and pharmaceutical industries. [6] No reports are available on the oxidation of alcohols into their carbonyl compounds catalysed by copper(II) Schiff base complexes in the presence of N-methylmorpholine-N-oxide (NMO) as co-oxidant. In copper (II) complexes the metal ions have either a four or six coordination geometry and there only a few exceptions to this.…”

Catalytic oxidation and C–C coupling reactions of new ruthenium(III) Schiff base complexes containing PPh3 or AsPh3 co-ligands

“…1 H-NMR spectra of all the Schiff bases were taken in DMSO d 6 . The aromatic region shows a set of multiplets in the range 7.0-8.0 ppm for all the Schiff bases.…”

“…In particular, triphenylphosphine complexes of ruthenium have been employed as catalysts for various organic transformations such as oxidation [5,6], hydrogenation [7], C-C couplings [8], hydroformylation [9], isomerization [10], polymerization [11], racemization [12], etc. Among these, catalytic oxidation of alcohols to carbonyl compounds is a pivotal reaction due to their utility in fine chemicals.…”

Biocidal and catalytic efficiency of ruthenium(III) complexes with tridentate Schiff base ligands

“…[16] For the o-aminobenzoic acid moiety, the free Schiff base H 2 L 3 shows a ν (O -H) absorption www.interscience.wiley.com/journal/aoc …”

“…Complexes showed redox couples with peak-to-peak separation values ( E p ) ranging from 29 to 765 mV, revealing that this process is at best quasi-reversible. [11,16] This is attributed to slow electron transfer and adsorption of the complex onto the electrode surface.…”