Willgerodt–Kindler reaction of arylglyoxals with amines and sulfur in aqueous media: a simple and efficient synthesis of α-ketothioamides

Abstract

A simple and efficient method for the synthesis of α-ketothioamides via the Willgerodt–Kindler reaction is developed. Reactions were carried out between arylglyoxal hydrates, amines and elemental sulfur in water at 80°C to afford corresponding α-ketothioamides in good to high yields in a short reaction time.

Keywords:

• Willgerodt–Kindler reaction
• α-ketothioamides
• arylglyoxals
• water
• sulfur

Acknowledgements

This work was partially supported by the research council of the University of Maragheh. B.E.S. gratefully acknowledges Mr Biglari (IASBS) for taking NMR spectra and Dr M. Rimaz (PNU) for preparing methoxy phenylglyoxals.