Selected Thoughts on Chiral Crystals, Chiral Surfaces, and Asymmetric Heterogeneous Catalysis



Although the uses of zeolitic materials in heterogeneous catalysis are extensive, the opportunity to develop applications of zeolites in enantioselective catalysis remains underexploited. In part, the relative paucity of chiral zeolite structures is one underlying reason, although some significant progress has been made in recent years in the preparation and structural characterization of chiral zeolitic materials, including the recent report of ITQ-37, the first example of a chiral mesoporous zeolite. However, as elaborated in this Minireview article, the preparation of a chiral zeolite structure is itself not sufficient to ensure that the material will be useful in enantioselective catalysis, and a number of other key issues must also be addressed. In addition to highlighting these issues, this Minireview surveys more widely a number of concepts that are pivotal to the design of chiral solids for the catalysis of enantioselective transformations. In addition to chiral zeolites, a range of other chiral materials, including organic molecular solids, and chiral catalysts, including metal–organic frameworks, chiral metal surfaces, and single-site immobilized organometallic species, are discussed, together with an appraisal of future directions for asymmetric heterogeneous catalysis.