Catalytic and Multicomponent Reactions for Green Synthesis of Some Pyrazolone Compounds and Evaluation as Antimicrobial Agents.

A green synthetic approach and facile method was developed to produce pyrazole compounds () by the reaction of ethyl acetoacetate (), hydrazines (), and catalytic imidazole () in aqueous media. 4-Dicyanomethylene-2-pyrazoline-5-one derivatives () were synthesized through the reaction of 2-pyrazoline-5-one derivatives () with tetracyanoethylene (TCE) () by using catalytic imidazole () in an aqueous medium. Moreover, the 4-dicyanomethylene derivative () was obtained via treatment of 1-phenyl-3,5-pyrazolidinedione (1) with TCE ().