Janusarene: A Homoditopic Molecular Host

We report a kind of homoditopic molecular host, janusarene, which has two back-to-back compactly arranged nanocavities for guest complexation. The unique two-face structural feature of janusarene allows it to bind and align various guest compounds, concurrently, which include the spherical pristine fullerene C60 and the planar polycyclic aromatic hydrocarbons (PAHs) such as pyrene, perylene, and 9,10-dimethylanthracene. The host-guest interactions were characterized by single crystal X-ray diffraction. A pairwise encapsulation of the PAH guests by janusarene enables us to obtain PAH dimers which deliver emerging spectroscopic properties distinct from those of PAHs dissolved in solution, or in the bulk state. Moreover, a monotopic control host was synthesized and used to characterize the host-guest complexing behaviour in solution.