(NH₄)₆Mo₇O₂₄·4H₂O as an Efficient, Selective, and Reusable Catalyst for the Oxidation of Thiols to Disulfides Using Potassium Bromate

Abstract

Ammonium molybdate, (NH₄)₆Mo₇O₂₄·4H₂O, is found to be an efficient and selective catalyst for the oxidation of thiols to corresponding disulfides using potassium bromate in aqueous acetonitrile as the solvent. Among various solvents tested, CH₃CN/H₂O showed better results in terms of the reaction yield and rate. In the absence of (NH₄)₆Mo₇O₂₄·4H₂O, the oxidation reaction is not selective for the formation of disulfides. The catalyst can be easily recovered after completion of the reaction and reused without any significant loss of its activity.

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GRAPHICAL ABSTRACT

Keywords:

• Ammonium molybdate
• oxidation of thiols to disulfides
• potassium bromate
• aqueous acetonitrile
• reusable catalyst

Acknowledgments

Support of this investigation by Ferdowsi University of Mashhad is gratefully acknowledged.