Selective stabilization of transition state structures for cope rearrangements of semibullvalene and barbaralane through interactions with halogens.
A new means-discovered through quantum chemical studies (B3LYP/6-31G(d))-of selectively stabilizing the delocalized forms of unsubstituted semibullvalene and barbaralane is described. Calculations indicate that complexation of delocalized semibullvalene and barbaralane Cope rearrangement transition structures by halogen-containing molecules (homo- and heteronuclear diatomics and Lewis acids) can reduce the barrier significantly, in many cases causing it to disappear entirely.
Wang
Selina C
SC
Department of Chemistry, University of California-Davis, One Shields Avenue, Davis, CA 95616, USA.
Tantillo
Dean J
DJ