One Pot Synthesis of Polyhydroquinolines Catalyzed by Sulfonic Acid Functionalized SBA-15 as a New Nanoporous Acid Catalyst under Solvent Free Conditions

Sulfonic acid functionalized SBA-15 (SBA-Pr-SO3H) as a new nanoporous acid catalyst was used in the one-pot synthesis of polyhydroquinolines derivatives via the Hantzsch four component condensation reaction of aldehydes, b-ketoesters, dimedone and ammonium acetate under solvent free conditions with short reaction time in excellent yields. SBA-Pr-SO3H was proved to be an efficient heterogeneous nanoporous solid acid catalyst (pore size 6 nm), which could be easily handled and removed from the reaction mixture by simple filtration, and also recovered and reused without loss of reactivity.