A Highly Pyramidalized Cage Alkene Formed via the Double Diels−Alder Cycloaddition of <i>syn</i>-4,5,13,14-Bis(dehydro)octafluoroparacyclophane to Anthracene

A double Diels−Alder reaction of the formal syn-bis(dehydro)octafluoroparacyclophane with anthracene leads to formation of a novel cage compound that contains a highly pyramidal double bond. The measures of pyramidality of this double bond constitute what appear to be the highest combined values of ψ and φ (34.3° and 33.5°, respectively) yet reported to have been determined by X-ray crystallography. This cage compound, although stable indefinitely as a crystalline compound in air, exhibits the high reactivity with both triplet and singlet O2 in solution that is characteristic of such highly pyramidal π systems.