Molding Clays into Efficient Catalysts

Esterification of dicarboxylic acids to diesters over Mn+-montmorillonite clay catalysts

“…The heterogeneous catalyst systems include cationic-exchanged resins like Amberlyst-15 [3], zeolites [4], metal oxides like sulphated zirconia and titania [5], heteropolyacids supported on silica and carbon [6], palladium on charcoal [7], silica chloride [8], aluminophosphate and silicoaluminophosphate molecular sieves [9], and cation exchanged montmorillonite K-10 [10]. In particular, the clay catalysts have received considerable attention in different organic syntheses because of their environmental compatibility, low cost, high selectivity, reusability and operational simplicity [11]. Among smectite clays, montmorillonite, both in natural and exchanged forms, possess both Lewis and Brønsted acidities, which enable them to function as efficient catalysts in organic transformations.…”

Efficient Prins cyclization in environmentally benign method using ion exchange resin catalyst

“…In recent years, the use of solid acidic catalysts such as amberlyst, clays, and zeolites has received considerable attention in different areas of organic synthesis because of their environment compatibility, reusability, high selectivity, operation simplicity, noncorrosiveness, low cost, and ease of isolation of the products (28,29). Prins-type cyclization reaction catalyzed by montmorillonite clay has been reported (30,31).…”

Esterification of succinic anhydride to di-(p-cresyl) succinate over Mn+-montmorillonite clay catalysts

“…The clay catalysts, in particular, have received considerable attention in different organic syntheses because of their environmental compatibility, low cost, high selectivity, reusability and operational simplicity [8]. Among smectite clays, montmorillonites, both in natural and exchanged forms, possess both Lewis and Brønsted acidities, which enable them to function as efficient catalysts in organic transformations.…”