Reusable (MWCNTs)-COOH/Fe3O4-CaO Magnetic Nanostructure Promoted Three-Component Synthesis of Hexahydroacridine Derivatives

(mwcnts)-cooh/fe3o4-cao magnetic nanostructure was employed for the high-yield synthesis of hexahydroacridine-1,8-dione derivatives via three-component reaction of dimedone, unprotected sugars, and aniline or 4-bromoaniline in ethanol under reflux conditions. (mwcnts)-cooh/fe3o4-cao was prepared by cooh functionalized multi-walled carbon nanotubes (mwcnts)-cooh with fe3o4-cao nanoparticles in the presence of feso4 and eggshell. this heterogeneous hybrid nanostructure, (mwcnts)-cooh/fe3o4-cao, was determined by sem, tem, xrd, edx, ft-ir, and tga. the potential application of this covalently linked basic catalyst was also investigated as an efficient, recyclable, and heterogeneous catalyst for the synthesis of hexahydroacridine-1,8-dione. the condensation of dimedone with unprotected sugars and aniline or 4-bromoaniline in the presence of a catalytic amount of (mwcnts)-cooh/fe3o4-cao magnetic nanostructure gave hexahydroacridine-1,8-dione derivatives in good yields. the products were identified by ft-ir, nmr spectra, and elemental analysis. the catalyst was separated by an external magnet from the reaction mixture, washed, and dried at 100 °c for 2 h. the recovered catalyst was then re-entered into a fresh reaction mixture and recycled 5 times without considerable loss of activity.