Calixarene based catalytic systems

Abstract

Catalysis is the essence of chemistry as it provides useful tools to make and brake chemical bonds. As nature has been a guide to many scientists, it’s no surprise that in the field of catalysis enzymes were a source of inspiration. Harnessing non covalent interactions, as enzymes do, is a fascinating perspective, and, since supramolecular chemistry became more and more involved in catalysis, a new discipline was born, named supramolecular catalysis. Since supramolecular hosts such as calix[n]arenes have been fruitfully employed in the synthesis of catalysts, in these work we report the design, characterization and applications of new calixarene based catalytic systems. In details chiral calix[4]arene amides 1-7 were employed as phase-transfer catalysts thanks to their cation complexing properties, while the calix[4]arene functionalized with a chiral primary amine-thiourea moiety 8 acted as bifunctional catalyst in several asymmetric conjugate addiction reactions. Finally dinuclear Zirconium-calix[8]arene complex 9 proved to be active in the ring opening polymerization of cyclic esters... [edited by Author]