ZrP 2 O 7 and CuFe 2 O 4 nanoparticles as e cient and reusable heterogeneous catalysts have been used for the preparation of 2H-indazolo[2,1-b]phthalazine-triones and 1H-pyrazolo[1,2-b]phthalazine-diones, respectively, under solvent-free conditions in good to excellent yields and short reaction times.