Base catalyzed reaction of 1,4-dithiane-2,5-diol with α-oxoketene dithioacetals: a new general method for the synthesis of 2-methylthio-3-aroyl/heteroaroyl thiophenes

The α-oxoketene dithioacetals and 1,4-dithiane-2,5-diol a dimer of mercapto acetaldehyde, react in the presence of anhydrous potassium carbonate in boiling ethanol to yield the corresponding 2-(methylthio)-3-aroyl/heteroaroyl thiophenes in 55–70% overall yields.