Synthesis and characterization of 4-methyl-1-(3-sulfopropyl)pyridinium hydrogen sulfate as a new ionic liquid immobilized on silica nanoparticles: A recyclable nanocomposite ionic liquid for the production of various substituted phthalazine-ones

摘要

4-Methyl-1-(3-sulfopropyl)pyridinium hydrogen sulfate ([MSPP][HSO4]) as a new acidic ionic liquid was prepared in a quick and easy process, and characterized by some techniques such as H-1 NMR, C-13 NMR and FT-IR analysis. Then, [MSPP][HSO4] was immobilized on silica nanoparticles by impregnation method to afforded heterogeneous acidic ionic liquid ([MSPP]HSO4@nSiO(2)) and characterized by elemental analysis (CHNS), FT-IR, and SEM. The worthiness of [MSPP]HSO4@nSiO(2) has been investigated for the synthesis of various substituted phthalazine-ones as well as selective synthesis of mono- and bis-phthalazine-ones as imperative biologically active compounds. The reaction has been carried out under solvent-free conditions, simple work-up procedure and the products were obtained in excellent to good yields. Moreover, the catalyst was reused five times without decay in catalytic activity performance. (C) 2018 Elsevier B.V. All rights reserved.