Copper-catalyzed efficient synthesis of 5-arylindazolo[3,2-b]quinazolin-7(5H)-ones from 2-nitrobenzaldehydes

Abstract A novel and practical copper-catalyzed approach was developed for the preparation of 5-arylindazolo[3,2- b ]quinazolin-7(5 H )-ones. The 2-amino- N′ -arylbenzohydrazideis easily prepared by a reaction of isatoic anhydride with arylhydrazine. Then, through a condensation/intramolecular cyclization reaction by 2-nitrobenzaldehydes in the present of CuI, the corresponding 5-arylindazolo[3,2- b ]quinazolin-7(5 H )-ones are produced in good yields.