Diazadioxacirculenes: Planar Antiaromatic Cyclooctatetraenes (pages 17097–17102)
Thomas Hensel, Denis Trpcevski, Christopher Lind, Rémi Grosjean, Dr. Peter Hammershøj, Dr. Christian B. Nielsen, Dr. Theis Brock-Nannestad, Bjarne E. Nielsen, Magnus Schau-Magnussen, Prof. Boris Minaev, Gleb V. Baryshnikov and Dr. Michael Pittelkow
Article first published online: 5 NOV 2013 | DOI: 10.1002/chem.201303194
Plane to see: New circulenes are planar when an adequate number of heteroatoms are in the outer ring. This leads to the antiaromatic nature of the central cyclooctatetraene ring. A new class of antiaromatic circulenes, the diazadioxacirculenes, have been prepared by means of a new acid-mediated oxidative dimerization of 3,6-dihydroxycarbazoles to yield the new circulenes in high yields (see scheme; R=benzyl or propyl).