An economic, simple and convenient synthesis of 2-aryl/heteroaryl/styryl/alkylbenzothiazoles using SiO2-HNO3

The present work was undertaken to develop an economic method for the synthesis of 2-aryl/heteroaryl/styryl/alkylbenzothiazoles mediated by SiO2-HNO3. In this report, we have demonstrated the catalytic potential of SiO2-HNO3 for the oxidative condensation of 2-aminothiophenol and aldehydes. Instant reaction at room temperature under solvent-free condition, high substrate to catalyst ratio 50:1 (by weight), practical application by large-scale synthesis, and excellent yields are the main advantages of the present protocol.