A one-pot synthesis of 2-amino- and 2-(arylamino)-substituted thiazoles and selenazoles using [hydroxy(tosyloxy)iodo]benzene, carbonyl compounds and thioureas or selenoureas: A modification of the Hantzsch synthesis

Article abstract of DOI:10.1055/s-1992-26243

A one-pot synthesis of 4-substituted 2-amino- or 2-(arylamino)thiazoles has been achieved via treatment of ketones with [hydroxy(tosyloxy)iodo]benzene and thioureas in refluxing acetonitrile. 1,3-Dicarbonyl compounds yield (5-acyl-4-methylthiazol-2-yl)ammonium tosylates and the corresponding selenazol-2-yl compounds, respectively, upon reaction with [hydroxy(tosyloxy)iodo]benzene followed by the addition of thiourea or selenourea. The tosylate salts are converted to the corresponding free bases by treatment with sodium bicarbonate. This synthesis is an important modification of the Hantzsch synthesis.