M. Sekota et T. Nyokong, CYCLIC VOLTAMMETRY AND SPECTROELECTROCHEMISTRY OF OSMIUM PHTHALOCYANINES IN AQUEOUS AND NONAQUEOUS SOLVENTS, Polyhedron, 15(17), 1996, pp. 2901-2908
Cyclic voltammetry of osmium phthalocyanine complexes, [(CN)(2)Os(II)P
c](2-) and (py)(2)Os(II)Pc (Pc = phthalocyanine dianion), show two oxi
dation couples and two reduction couples in acetonitrile and dimethylf
ormamide. Oxidation and reduction in these complexes occur at the ring
to form cation and anion radical species, respectively. The [(CN)(2)O
s(II)Pc](2-) complexes show a remarkable ease of ring oxidation with o
xidation potentials that are much lower than is typical for metallopht
halocyanines. Half-wave potentials of 0.25 and 0.67 V (versus saturate
d calomel electrode, SCE) were obtained for the first and second ring
oxidations, respectively. The [(CN)(2)Os(II)Pc](2-) complex is soluble
in water at pi-Is greater than 4. This complex shows one oxidation co
uple in pH 9 buffer at -0.11 V versus SCE. Copyright (C) 1996 Elsevier
Science Ltd