To this end, we focused on compounds 8-12 (Figure ). The water-insoluble guests triphenylphosphine oxide 8, phenolphthalein 9, and tetrakis(4-hydroxyphenyl)methane 10 were added to aqueous solutions of T in excess, and the resulting suspensions were stirred at 60 ºC. The reactions were quenched after different times by cooling to room temperature, removing undissolved (i.e., unencapsulated) solids by filtration, and evaporating water. The residue was dissolved in D2O and analyzed by 1 H NMR spectroscopy. To our satisfaction, we found that 8, 9, and 10 converted cage T into C in 90%, 94%, and 100% yield, respectively. In all cases, the conversion was complete within 16 h (Figures and).