Bennett, Deon A.; Dasgupta, Tara P.; Stedman, Geoffrey
Author Affiliation, Ana.
Department of Chemistry
Redox chemistry of [Fe2(CN)10]4–. Part 5. Reaction with thiourea
Transition Metal Chemistry
Date of Publication
The reaction of the dimeric iron(III) complex [Fe2(CN)10]4- with a large excess of thiourea, tu, takes place in a series of stages, the first two of which have been examined in detail. The first stage is a one equivalent outer sphere electron transfer to form [Fe2-(CN)10]5- and the radical cation tu+· which dimerises to form the disulfide tu2+2. There is kinetic evidence for the formation of a significant proportion of a precursor complex [Fe2(CN)104-.tu at high concentrations of tu. The second stage involves cleavage of the mixed valence dimer to yield [Fe(CN)5tu]2- and [Fe(CN)5H2O]3-. On standing, substitution of H2O by tu and oxidation by air occurs slowly, and finally all of the original iron is observed as [Fe(CN)5tu]2-.....