Introduction of a new catalyst containing an ionic liquid bridge on nanoporous Na+- montmorillonite for the synthesis of hexahydroquinolines and 1,8-dioxo-decahydroacridines via Hantzsch condensation

A new nanoporous catalyst formulated as Na+-MMT-[bip]-NH2+ HSO4− is prepared via modification of Na+-MMT with bis-3-(trimethoxysilylpropyl)-amine and then addition of sulfuric acid. In continue the prepared reagent is identified with different methods including Fourier-transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscopy (FESEM), thermogravimetric analysis (TGA), transmission electron microscopy (TEM), energy dispersive spectrometer (EDS) and CHN elemental analysis. After identification the catalytic efficiency of this reagent is tested in the synthesis of hexahydroquinolines and 1,8-dioxo-decahydroacridines via Hantzsch condensations. All reactions are performed under mild conditions in the absence of solvent in high yields in short reaction times. The catalyst is also reusable for several times in both of the studied reactions. [Display omitted] •Easy preparation and identification of nanoporous Na+- montmorillonite modified whit bis-3-(trimethoxysilylpropyl)-ammonium hydrogen sulfate (Na+-MMT-[bip]-NH2+ HSO4−).•High stability of Na+-MMT-[bip]-NH2+ HSO4− even after several months.•Application of Na+-MMT-[bip]-NH2+ HSO4− for the synthesis of hexahydroquinoline and 1,8-dioxo-decahydroacridine derivatives via Hantzsch condensation.•No side reactions, ease of preparation and handling of the catalyst, facilitate the separation of the product from the catalyst.•Reusability of the catalyst.