Cu(ClO(4))(2)-mediated arene C-H bond halogenations of azacalixaromatics using alkali metal halides as halogen sources.

Regiospecific halogenation of azacalix[1]arene[3]pyridines at the lower rim position of the benzene ring was achieved from their cross-coupling reaction with cost-effective alkali metal halides 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-X bond formation reaction under very mild conditions.