Acidic ionic liquids are an important and wide category of ionic liquids that have one or more acidic active sites in their structure. Increasing interest in ionic liquids by chemists and technologists is due to the use of ionic liquids for chemical reactions, including catalytic reactions. In the first part, Bronsted acid ionic liquids [DMAP-SO3H]Cl and [DMAP-H]HSO4 were synthesized and identified using FT-IR and NMR spectra. Then, it was used as a catalyst in the synthesis of 3-substituted indole derivatives using a one-pot and three-component reaction of indole, aromatic aldehydes, and malononitrile (Scheme 1). In the second part, the synthesis of magnetic ionic liquid Mn-CoFe2O4@Niacin-SO3H was done and it was identified using FT-IR, FE-SEM, EDS, XRD, TGA-DTG, and VSM analyses. Next, its catalytic activity was investigated in the preparation of tetrahydrodipyrazolopyridine derivatives (Scheme 2), pyranopyrazole (Scheme 3), 1, 4-dihydropyridine (Scheme 4), and dihydropyrimidinone (Scheme 5). The use of green solvents and solvent-free conditions, high efficiency, short reaction time, easy separation of products and the ability to reuse the catalyst are among the advantages of these reactions.
