678140-49-3Relevant academic research and scientific papers
Synthesis, characterisation and redox behaviour of mixed ligand complexes of osmium(II/III/IV)
Chowdhury, Habibar,Bose, Doyel,Rahaman, Sk. Hafijur,Ghosh, Barindra Kumar
, p. 2772 - 2777 (2007/10/03)
A group of mixed-tris chelates of osmium(II), (III) and (IV) of the general formula [OsL′L2]2+ [L′ = N-((pyridin-2-yl)formylidene)aniline (pfan) or N-((pyridin-2-yl)benzylidene)aniline (pban); L = 2,2′-bipyridyl (bipy), 2-(m-tolylazo)pyridine (tapy) or quinolin-8-olate (oxin); z = 1-3] have been prepared, isolated as their perchlorates and characterised by physicochemical, magnetic and spectroscopic methods. The complexes exhibit several spin-allowed and spin-forbidden charge-transfer transitions in the 1000-200 nm region. In MeCN solutions the chelates display osmium(IV)-osmium(III) and osmium(III)-osmium(II) couples in the range -0.4 to 1.6 V vs SCE. The stability of metal oxidation levels is discussed in terms of the electrochemical results and correlated to the π-acceptor properties of these ligands. On the negative side of SCE, successive ligand reductions in bipy/tapy complexes are observed involving diimine (-N=C-C=N-)/azoimine (-N=N-C=N-) group.
