One-pot pseudo five-component synthesis of some new, vital and pharmaceutically important bis 1HIndazolo [1,2-b]phthalazine-triones has been considered in presence of prepared NiFe2O4@TiO2-DEAOSO3H nanostructure as an efficient magnetic nanocatalyst. The synthesized compounds can be good candidates to have diverse biological potency and efficacy. The geometry, electronic structure, natural bond orbitals (NBO) and molecular electrostatic potential (MEP) surface analysis were carried out for some bis 1H-Indazolo [1,2-b]phthalazine-triones using HF/3-21G computational method. The theoretical studies revealed the existense of intramoleculare hydrogen bonds and high HOMO-LUMO energy gap for the products structures. Some advantages of this protocol are high yields, short reaction times, simple purification, and environmentally mild reaction conditions. Furthermore, the catalyst was reused at least six times without substantial loss of catalytic activity