Calix[6]resorcinarenes: the first examples of [16]metacyclophanes derived from resorcinols

Abstract

The cyclocondensation of 2-alkylresorcinols with 1,3,5-trioxane in ethanol–conc. HCl (4:1 v/v) produced calix[4]resorcinarene and calix[6]resorcinarene; the latter was isomerized to the former on prolonged heating in the reaction media.