Castro, C., Isborn, C. M., Karney, W. L., Mauksch, M., & {Von Ragué Schleyer}, P. (2002). {Aromaticity with a twist: Möbius [4n]annulenes}. Organic Letters, 4, 3431–3434. Abstract
Aromatic Möbius [4n]annulenes with 4n pi electrons, originally conceived by Heilbronner, are characterized computationally. These (CH)(12), (CH)(16), and (CH)(20) minima have nearly equal C-C bond lengths, small twist angles around the rings, and magnetic properties (NICS, nucleus-independent chemical shifts–see above at various positions in [16]annulene–and magnetic susceptibility exaltations) indicating significantly diatropic ring currents. The Möbius forms are not the most stable isomers but may contribute significantly to the chemistry of these annulenes. [structure: see text]