Inhibition by Water during Heterogeneous Brønsted Acid Catalysis by Three-Dimensional Crystalline Organic Salts

A new self-assembled and self-healing class of metal free, recyclable, heterogeneous Brønsted acid catalysts has been developed by the protonation aniline derivatives (tetrakis(4-aminophenyl)methane, leuco-crystal violet, benzidine, p-phenylenediamine) with aromatic sulfonic acids (tetrakis(phenyl-4-sulfonic acid)methane, 2,6-naphthalenedisulfonic acid). As a result, five three-dimensional crystalline organic salts (F-1a, F-1b, F-1c, F-2, F-3) were obtained, linked hydrogen bonds additionally stabilized opposite charges components. Frameworks F-2 F-3 prepared for first time characterized elemental analysis, X-ray structural analysis (for F-2), thermogravimetry, SEM, FTIR spectroscopy. The catalytic activities F-1–3 have explored in industrially important epoxide ring-opening acetal formation reactions. presence encapsulated water inside frameworks F-1a had an inhibitory effect on performance catalysts. diffraction hydrated dehydrated samples indicated that crystallization served as cross-linking agent, diminishing substrate induced “breathing” affinities frameworks.