Vanadium(V)/vanadium(III) redox couple in acidic organic media. Structure of a vanadium(III)-tetraethylene glycol pentagonal-bipyramidal complex ([V(teg)(Br)2]+Br-)

Ronny Neumann, Igal Assael

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The vanadium(V)/vanadium(III) redox couple was investigated in an acidic organic medium by reduction of sodium metavanadate by hydrogen bromide with 1,2-dichloroethane as solvent in the presence of tetraglyme as a complexing agent. In the absence of dioxygen a vanadium(III)-tetraethylene glycol (teg) pentagonal-bipyramidal complex, [V(teg)(Br)2]+Br-, is formed. In the presence of dioxygen a catalytical cycle is initiated whereby vanadium(V) oxidizes hydrogen bromide to molecular bromine. The reduced vanadium(III) species thereby formed is reoxidized by dioxygen to vanadium(V) as confirmed by ESR and UV-vis of the organic phase.

Original languageEnglish
Pages (from-to)8410-8413
Number of pages4
JournalJournal of the American Chemical Society
Issue number22
Publication statusPublished - 1989


ASJC Scopus subject areas

  • Chemistry(all)

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