A Facile Method for the Synthesis of Thiocoumestan Derivatives

An efficient synthesis of thiocoumestan derivatives, starting from catechols and 4-mercaptocoumarin in the presence of potassium ferricyanide as an oxidizing agent (Decker oxidation) was developed. The results indicate that the 4-mercaptocoumarin participates in Michael addition reactions with in situ generated o-benzoquinones. The present work has led to the development of a one-pot oxidative method for the synthesis of the 6H-benzothieno[3,2-c][1]benzopyron-6-one derivatives.