Solution-phase molecular recognition of an azafullerene-quinoline dyad by a face-to-face porphyrin-dimer tweezer

First Synthesis of the Inherently Chiral Trans-4' Bisadduct of C59 N Azafullerene by Using Cyclo-[2]-dodecylmalonate as a Tether

The multiaddition chemistry of azafullerene C₅₉ N has been scarcely explored, and the isolation of pure bisadducts is in its infancy. Encouraged by the recent regioselective synthesis of the inherently chiral equatorial_face bisadduct of C₅₉ N, we focused on the isolation of the first trans-4 bisadduct in a simple two-step approach. The first regioselective synthesis of the trans-4 bisadduct of C₅₉ N by using cyclo-[2]-dodecylmalonate as a tether is now reported. The newly synthesized bisadduct has C₁ symmetry, as evidenced by ¹³ C NMR, while X-ray crystallography validated the trans-4' addition pattern. Furthermore, the inherently chiral trans-4' C₅₉ N bisadduct was enantiomerically resolved, and the mirror-image relation of the two enantiomers was probed by circular dichroism spectroscopy. Finally, UV-Vis and redox assays suggested that the addition pattern has a reflection in the light-harvesting and redox properties of the bisadduct.