SELECTIVE FUNCTIONALIZATION OF CALIX[4]ARENES AT THE UPPER RIM

Methods are described for the selective diametrical functionalization of calix[4]arenes at the upper rim, either by the selective removal of the p-tert-butyl groups and subsequent substitution at the free phenol rings or by selective reactions at the phenol rings of dialkoxycalix[4]arenes without the tert-butyl groups. This includes selective mercuration and the synthesis of 5,17-di-£erf-butyl-26,28-dimethoxy-ll,23-diphenylcalix[4]arene (13), of which the crystal structure is described. The first synthesis of macrocyclic diquinones derived from calix[4]arenes (calix[4]diquinones) is described. © 1990, American Chemical Society. All rights reserved.