title: Evidence for the cyclic CN2 carbene in the gas phase.
abstract: 3-Halodiazirine-3-carboxylic acids (c-CN2XCOOH, X = Cl or Br) were prepared from their esters and converted to the corresponding sodium salts. Collision-induced dissociation (CID) of the carboxylate ions led exclusively to the loss of CO2 and the resulting c-CN2X(-) ions dissociated to c-CN2 carbene at low energies. The bond dissociation energy (BDE) for c-CN2Br(-) was found to be less than 8 kcal/mol using CID of the anion generated by electrospray ionization of the carboxylate. The analogous difluoro system (CF2XCOOH/CF2X(-)/CF2) exhibits similar dissociative behavior. All experimental BDEs are in very good agreement with MP4/aug-cc-pVTZ calculations.
authors.affiliation: Department of Organic Chemistry, University of Chemical Technology , Technická 5, 166 28 Prague, Czech Republic.
authors.forename: Eva
authors.initials: E
authors.lastname: Hanzlová
authors.forename: Jiří
authors.initials: J
authors.lastname: Váňa
authors.forename: Christopher J
authors.initials: CJ
authors.lastname: Shaffer
authors.forename: Jana
authors.initials: J
authors.lastname: Roithová
authors.forename: Tomáš
authors.initials: T
authors.lastname: Martinů