Zeng, TaoRawashdeh, Abdel MonemChakkingal Parambil, PriyakumariHoffmann, Roald2020-04-032020-04-032017A. M. Rawashdeh, P. C. Parambil, T. Zeng, R. Hoffmann. “An iodabenzene story.” Journal of the American Chemical Society 2017, 139, 7124-7129.https://doi.org/10.1021/jacs.7b03388https://hdl.handle.net/10315/37163We call iodabenzene a cyclic (CH)5I molecule. A planar iodabenzene would have 8 π electrons, a situation best avoided by an out-of-plane distortion to a bird-like geometry. The electronic structure and charge distribution of this molecule resemble those of Meisenheimer complexes, derivatives of (CH)5CH2–. A similar substitution strategy, of π-acceptors in ortho and para positions, works in both cases to planarize and stabilize such derivatives. Some 40 kcal/mol (73 kcal/mol for the unsubstituted case) below the bird, a classical 5-iodocyclopentadiene structure awaits, reached through a bicyclic transition state. The calculated activation barrier for the highly exothermic reaction to a classical Lewis structure nevertheless make us optimistic about the chances of detecting and even isolating the bird isomer.enArticlehttps://pubs.acs.org/doi/abs/10.1021/jacs.7b03388