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

Chemistry. 2021 Oct 1;27(55):13879-13886. doi: 10.1002/chem.202101776. Epub 2021 Aug 31.

Abstract

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 equatorialface 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.

Keywords: azafullerenes; bisadducts; cyclo-[2]-malonates; regioselectivity; tether-directed remote functionalization.

MeSH terms

  • Crystallography, X-Ray
  • Fullerenes*
  • Magnetic Resonance Spectroscopy
  • Stereoisomerism

Substances

  • Fullerenes