Calix[4]arenes, bridged at the upper rim

Abstract

Calix[4]arenes, in which two opposite p-positions are linked by an aliphatic chain, and their derivatives show transport or complexation properties strongly dependent on the length of this chain. Bicyclo-calix[4]arenes, a special case of 1,3-bridged calix[4]arenes, and annelated calix[4]arenes, a special case of 1,2-bridged calix[4]arenes, are also described. © 1993 IUPAC