An Oxidative Macrobicyclic Ring Opening of a Triptycene to a Highly Functionalized Fluorene Derivative

The treatment of hexamethoxytriptycenes with nitric acid leads to an unprecedented oxidative ring opening of the triptycene scaffold, resulting in a new class of fluorene derivatives with a nitroquinone unit. Preliminary investigations of the influence of chain length of alkyl substituents at the triptycene bridgeheads to the reaction have been performed, revealing that exclusively the methyl-substituted hexamethoxytriptycene does not undergo an oxidative ring opening reaction.