Journal of the American Chemical Society, Vol.139, No.51, 18508-18511, 2017
Chiral Nanographene Propeller Embedding Six Enantiomerically Stable [5]Helicene Units
A one-step synthesis of a nanographene propeller with a D-3-symmetry was obtained starting from 7,8-dibromo[5]helicene by Yamamoto nickel(0) couplings. It afforded a chiral polyaromatic hydrocarbon (PAH) embedding six enantiomerically stable [5]helicene units. This dense accumulation of helical strain resulted in a distorted geometry, but stable stereochemistry. The conformational, structural, chiroptical, and photophysical properties of the molecule are reported.