Encapsulation of Anionic guests in a New Hydantoinylamido Molecular Capsule

Resorcin[4]arene-based tetrakis(N-hydantoinylamido)cavitand 1 forms a stable molecular capsule in the presence of suitable anionic guests such as CH3OSO3 – or BF4 – in C2D2Cl4. Molecular capsule G2@1 2 is stabilized by the eight intermolecular imide N-H···OC hydrogen bondings, two from each four paired hydantoinyl units, and the eight intramolecular amide N-H···O–CH2-O hydrogen bondings, four on each two cavitands. The formations of molecular capsules were confirmed by 1H, 2D NOESY, and 2D-DOSY NMR.