Synthesis, conformational and host–guest properties of water-soluble pillar[5]arene

Abstract

Water-soluble pillar[5]arene was synthesized by the introduction of carboxylate anions at both upper and lower rims. When cationic viologen salt was mixed with the water-soluble pillar[5]arene in aqueous media, a very stable 1:1 host-guest complex was formed.