title: Carbo-quinoids: stability and reversible redox-proaromatic character towards carbo-benzenes.
abstract: The carbo-mer of the para-quinodimethane core is stable within in a bis(9-fluorenylidene) derivative. Oxidation of this carbo-quinoid with MnO2 in the presence of SnCl2 and ethanol affords the corresponding p-bis(9-ethoxy-fluoren-9-yl)-carbo-benzene. The latter can be in turn converted back into the carbo-quinoid by reduction with SnCl2 , thus evidencing a chemical reversibility of the interconversion between a pro-aromatic carbo-quinoid and an aromatic carbo-benzene, and is reminiscent of the behavior of the benzoquinone/hydroquinone redox couple (in the red-ox opposite sense).
authors.affiliation: CNRS, LCC (Laboratoire de Chimie de Coordination), 205 route de Narbonne, BP44099, 31077 Toulouse Cedex 4 (France); Université de Toulouse, UPS, ICT-FR 2599, 31062 Toulouse Cedex 9 (France).
authors.forename: Kévin
authors.initials: K
authors.lastname: Cocq
authors.forename: Valérie
authors.initials: V
authors.lastname: Maraval
authors.forename: Nathalie
authors.initials: N
authors.lastname: Saffon-Merceron
authors.forename: Alix
authors.initials: A
authors.lastname: Saquet
authors.forename: Corentin
authors.initials: C
authors.lastname: Poidevin
authors.forename: Christine
authors.initials: C
authors.lastname: Lepetit
authors.forename: Remi
authors.initials: R
authors.lastname: Chauvin
keywords: X-ray diffraction; alkynes; aromaticity; heterocycles; quinodimethanes