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Aromaticity with a twist: Möbius [4n]annulenes. | LitMetric

Aromaticity with a twist: Möbius [4n]annulenes.

Org Lett

Department of Chemistry, University of San Francisco, 2130 Fulton Street, San Francisco, CA 94117, USA.

Published: October 2002

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]

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Source
http://dx.doi.org/10.1021/ol026610gDOI Listing

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