Electrostatic co-assembly of pillar[n]pyridiniums and calix[4]arene in aqueous media

Abstract

Cationic pillar[n]pyridiniums and anionic p-sulfonatocalix[4]arene co-assemble into all-organic supersalts through encaging of the supercation units within/between the capsules that emerge from superanion pairs. The encapsulation occurs both in the solid state and in solution and allows the base-sensitive cationic pillar[n]pyridiniums to survive under otherwise destructive conditions. This property of supersalts makes them promising repositories for chemically vulnerable charged entities.