Easy and efficient one-pot synthesis of pyrazolo[1,5-c]quinazolines under mild copper-catalyzed conditions

An easy and efficient method has been developed for the synthesis of pyrazolo[1,5-c]quinazolines via one-pot two-step reactions of readily available substituted 1-(2-halophenyl)-3-akylprop-2-yn-1-ones, hydrazine hydrochloride and amidine hydrochlorides under mild conditions, and the corresponding pyrazolo[1,5-c]quinazolines were obtained in good to excellent yields. The novel method affords a new strategy for the construction of diverse and useful poly N-heterocyclic compounds.