title: Extraordinary modes of bonding enabled by the triquinane framework.
abstract: Incorporation of triquinane ring systems into a macrobicyclic framework enables the stabilization of unusual bonding arrangements, including 3-center-2-electron cation, 3-center-3-electron radical, and 3-center-4-electron anion systems, linear divalent fluorine, triplet carbenes, record short C-C bonds, a powerful proton sponge effect, and oxadionium (R4O(2+)) ions. The means to stabilize and conceivably isolate such species derives from the rigid, convex nature of the triquinane ring system, as well as the substitution of positions adjacent to the bridgeheads atoms which would otherwise be vulnerable to elimination. The potential realization of hitherto undescribed bonding outcomes makes these macrocycles provocative synthetic targets.
authors.affiliation: Department of Chemistry, University of California Davis , 1 Shields Avenue, Davis, California 95818, United States.
authors.forename: Gorkem
authors.initials: G
authors.lastname: Gunbas
authors.forename: Mark
authors.initials: M
authors.lastname: Mascal