N-Methylpyridinium tosylate catalyzed green and efficient synthesis of some novel 2,4-disubstituted thiazoles and 4-thiazolidinones

A convenient solvent less cyclocondensation from thiosemicarbazone of benzofuranone and chloroacetic acid using an ionic liquid, N-methylpyridinium tosylate for obtaining novel 4-thiazolidinones in excellent yields is reported. Also, the green expedient synthesis of new 2,4-disubstituted thiazoles under grinding condition from phenacyl bromides and thiosemicarbazide derivatives in quantitative yields is reported.