Acidic ionic liquid-functionalized ordered mesoporous polymers: Highly efficient solid acid catalysts for water-medium organic reactions

Strong acidic ionic liquid-functionalized mesoporous organic material (MPOM-T-AIL) has been created by quaternary ammonization of mesoporous organic material (MPOM) with 1,3-propane sultone and subsequent strong acid (H2SO4 or HSO3CF3) acidification. The novel supporting material, MPOM, had high nitrogen content and was synthesized by direct high-temperature (400-550 degrees C) polymerization of an easily prepared and low cost protic salt [pPDA][2HSO4], which was obtained by simple neutralization of p-phenylenediamine with two equivalents of H2SO4. MPOM-T-AIL possesses high BET specific surface area, ordered and uniform mesoporosity, hydrophobic property, and highly active acidic ionic liquid components. Catalytic tests in the water-medium Prins reactions and acetalization of benzaldehyde with ethylene glycol showed that MPOM-T-AIL exhibits much better catalytic activities and reusabilities than commercially available solid acid catalysts Amberlyst 15 and H-ZSM-5, and mineral acid H2SO4. Additionally, MPOM-T-AIL significantly improved the catalytic selectivity of the water-medium Prins reaction, which was strongly related to its hydrophobic property. MPOM-T-AIL with excellent catalytic performance is a promising new solid acid catalyst for various acid-catalyzed reactions.