A Simple and Efficient Synthesis of 3-(3-Phenyl-7H-[1,2,4]triazole[3,4][1,3,4]thiadiazin-6-yl)chromen-2-ones

Abstract

The compounds 3-(3-phenyl-7H-[1,2,4]triazole[3,4][1,3,4]thiadiazin-6-yl)chromen-2-ones (3), have been prepared by the condensation of 3-(2-bromoacetyl)chromen-2-ones (1) with 4-amino- 5-phenyl-4H[1,2,4]triazole-3-thiols (2), under reflux in ethanol. A simple and efficient procedure has also been developed involving a green method wherein 3 was obtained by physical grinding of 1 with 2 in the presence of K₂CO₃ as base and tetrabutyl ammonium bromide as surface catalyst, in a mortar and pestle. The latter procedure has been found to be much more efficient in terms of time and yield. The structures of all the compounds have been established on the basis of their spectral and analytical data.