Reversible encapsulation by self-assembling resorcinarene subunits

Encapsulation complexes are assemblies in which a reversibly formed host mo re or less completely surrounds guest molecules. Host structures held toget her by hydrogen bonds have lifetimes in organic solvents of milliseconds to hours, long enough to directly observe the encapsulated guest by NMR spect roscopy. We describe here the action of alkyl ammonium compounds as guests that gather up to six molecules of the host module to form encapsulation co mplexes. The stoichiometry of the complexes - the largest hydrogen-bonded h ost capsules to date - is determined by the size and concentration of the g uest.