Are antiaromatic rings stacked face-to-face aromatic?
The stacking of 4n pi electron hydrocarbon rings into superphane structures can eliminate their antiaromaticity and result in through-space three-dimensional aromatic character. This is demonstrated by the bond length equalized geometries and diatropic NICS values of the methano-bridged superphane series with interacting three- to nine-membered 4n pi electron rings. Along with triplet and Möbius strategies, stacking is the third way to achieve aromatic ring systems with 4n pi electrons.
Department of Chemistry and Center for Computational Chemistry, University of Georgia, Athens, Georgia 30602, USA.
Clémence
C
Corminboeuf
Paul von Ragué
Pv
Schleyer
Philip
P
Warner