design, characterization and application of so3h-functionalized phthalimide as a highly efficient catalyst for the condensation of dimedone with arylaldehydes, β-ketoesters and ammonium acetate

in this work, so3h-functionalizedphthalimide (sfp) as a so3h-containing solid acid is prepared by the reaction of phthalimide with chlorosulfonic acid, and characterized by ft-ir, 1h and 13c nmr, mass, tg, dtg, xrd and sem. then, it is utilized as a highly efficient, heterogeneous and green catalyst for the one-pot multi-component condensation of dimedone with arylaldehydes, β-ketoesters and ammonium acetate under solvent-free conditions to afford polyhydroquinolines in excellent yields and in short reaction times.