Regiospecific functionalization of azacalixaromatics through copper-mediated aryl C-H activation and C-O bond formation

Regiospecific functionalization of tetraazacalix1]arene3]pyridines at the lower rim position of the benzene ring was achieved conveniently from their cross-coupling reaction with both aliphatic alcohols including chiral primary and secondary alcohols and phenol derivatives through the Cu(ClO(4))(2)-mediated aerobic aryl C-H activation, which gave structurally well-defined aryl-Cu(III) intermediates and a subsequent C-O bond formation reaction under very mild conditions.