An efficient ultrasound-promoted one pot synthesis of spiroacenaphthylene pyrazolotriazole and pyrazolophthalazine derivatives

A facile and efficient one pot three-component ultrasound-promoted synthesis of spiro pyrazolo compounds has been developed. Employing ethanol as a solvent, assumed to be relatively environmentally benign, and use of an inexpensive and readily available catalyst combined with the advantages of sonochemistry, such as mild reaction conditions, excellent yield, and short reaction times highlight this synthetic route. The reactions were carried out under both conventional heating and ultrasound-assisted conditions and several reaction parameters are investigated and compared.