An efficient and green one-pot synthesis of indazolo[1,2-b]-phthalazinetriones via three-component reaction of aldehydes, dimedone, and phthalhydrazide using Fe3O4@SiO2 core-shell nanoparticles

An efficient and eco-friendly procedure for the one-pot synthesis of biologically active heterocyclic compounds including indazolo[1,2-b]-phthalazinetriones has been developed in the presence of Fe3O4@SiO2 nanoparticles. The multicomponent reactions of aldehydes, dimedone, and phthalhydrazide were carried out under solvent-free conditions to obtain some indazolo[1,2-b]-phthalazinetrione derivatives. The present approach provides several advantages such as excellent yields, a simple workup, low reaction times, easy catalyst separation, and little catalyst loading.