Supramolecular Subphthalocyanine Cage as Catalytic Container for the Functionalization of Fullerenes in Water.

Herein we report the first example of a supramolecular cage that works as a catalytic molecular reactor to perform transformations over fullerenes in aqueous medium. Taking advantage of the ability of metallo–organic Pd(II)‐subphthalocyanine (SubPc) capsules to form stable host:guest complexes with C60, we have prepared a water‐soluble cage that provides a hydrophobic environment for conducting cycloadditions over encapsulated C60, namely, Diels–Alder reactions with anthracene. Indeed, the presence of catalytic amounts of SubPc cage dissolved in water promotes co‐encapsulation of insoluble C60 and anthracene substrates, allowing the reaction to occur inside the cavity under mild conditions. The lower stability of the host:guest complex with the resulting C60 cycloadduct facilitates its displacement by pristine C60, which grants catalytic turnover. Moreover, bis‐addition compounds are regioselectively formed inside the cage when using excess anthracene. [ABSTRACT FROM AUTHOR]