An Efficiently Sonochemical Synthesis of Novel Pyrazoles, Bipyrazoles and Pyrazol-3- ylPyrazolo[3,4-d]pyrimidines Incorporating 1H-benzoimidazole Moiety

Novel pyrazoles, bipyrazoles and pyrazol-3-ylpyrazolo[3,4-d]pyrimidines were synthesized using the versatil synthon 2-(1H-benzimidazol-2-yl)-3,3-bis(methylthio) acrylonitrile (1). Reactions were carried out under silent and ultrasonic conditions. In general, improvement in rates and yields were observed when reactions were carried out under ultrasonic irradiation compared with silent condition. Structures of the products were established on analytical and spectral data.