Calixhydroquinones: a novel access to conformationally restricted, meta-substituted calixarenes†

Abstract

An efficient and versatile synthetic route to calixhydroquinones is described. These macrocycles are activated towards meta substitution, and reaction with bromine gives the first examples of persubstituted, phenol-derived calixarenes. The effect of meta substitution on calixarene mobility is demonstrated by the fixation of an otherwise mobile calix[4] system in the partial cone conformer, and the slowing of the ring inversion rate in calix[8]arenes.