Transition Metal Chemistry

, Volume 6, Issue 4, pp 230–234 | Cite as

The Kinetics and mechanisms of oxidation of dihydroxybenzenes by ethylenediaminetetraacetatomanganate(III)

  • Gianfranco Giraudi
  • Edoardo Mentasti
Full Papers

Summary

The kinetics and mechanism of oxidation of 1,4-dihydroxybenzene (H2Q), 2,5-dihydroxybenzenesulphonic acid (H2SQ) and 4,5-dihydroxy-1,3-benzenedisulphonic acid (H2T) to the correspondingortho orPara-quinones by ethylenediaminetetraacetatomanganate (III) has been investigated over the 2.5–6.0 pH range, at 20.0° by the stopped-flow technique. Complex behaviour is observed for H2Q due to the superposition of the precursor complex formation and the redox act, while at higher pH's these reactions separate. For the other substrates, a single second order step (first order in each reactant) was present whose rate showed different pH dependences. All these features are discussed with reference to the reduction potential of the substrates, their acidity and coordinating ability.

Keywords

Oxidation Physical Chemistry Inorganic Chemistry Acidity Complex Formation 

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Copyright information

© Verlag Chemie GmbH 1981

Authors and Affiliations

  • Gianfranco Giraudi
    • 1
  • Edoardo Mentasti
    • 1
  1. 1.Istituto di Chimica AnaliticaUniversità di TorinoTorinoItaly

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