A facile one-pot synthesis of thiazoles and thiazolyl-pyrazole derivatives via multicomponent approach

Thiazoles and thiazolyl-pyrazole derivatives have been efficiently synthesized under neat reaction conditions in excellent yields. Condensation of 3-(2-bromoacetyl)-4-hydroxy-6-methyl-2H-pyran-2-one (1), thiosemicarbazide (2) and various carbonyl compounds (3 & 5) gave corresponding thiazole (4) and thiazolyl-pyrazole derivatives (6) in excellent yields by using Hantzsch-Thiazole synthesis. The main advantage of this method is the short reaction time, high yields, simple workup and environmental benign process. The structures of newly synthesized compounds have been established by elemental analysis and spectral data.