Guest loading, chromatographic purification and controlled release from kinetically trapped, hydrogen-bonded pyrogallol[4]arene capsules

Pyrogallol[4]arene and hydrocarbon guest molecules form kinetically trapped encapsulation complexes when assembled in the absence of solvent. While solvent encapsulation complexes are more stable, these pre-loaded capsules can be purified by gel permeation chromatography and guest release can be induced later, at a chosen time, by heating. This result is the first example of chromatographic purification and subsequent guest release from kinetically trapped, artificial, hydrogen-bonded molecular capsules.