Organic synthesis using clay and clay-supported catalysts

Clays and modified clays are used to catalyze various types of organic reactions such as addition, Michael addition, carbene addition and insertion, hydrogenation, allylation, alkylation, acylation, pericyclic reactions, condensation reactions, aldol formation, imine synthesis, diazotization reactions, synthesis of heterocycles, esterification reactions, rearrangement/isomerization reactions, cyclization reactions, oxidation of alcohols, dehydrogenation, epoxidation and several more. Clays function as Brّnsted and/or Lewis acids, or as bases. Clays with combined acidic and basic properties have been developed by simple procedures of modification. Such clays are employed to catalyze a sequence of acid and base-catalyzed reactions in one pot. Good enantioselectivity and stereoselectivity are achieved using chiral organic compounds and chiral complexes intercalated between clay layers. Examples from recent literature are described here.