Abstract
3-Halodiazirine-3-carboxylic acids (c-CN2XCOOH, X = Cl or Br) were prepared from their esters and converted to the corresponding sodium salts. Collisioninduced dissociation (CID) of the carboxylate ions led exclusively to the loss of CO2 and the resulting c-CN2XMINUS SIGN ions dissociated to c-CN2 carbene at low energies.
The bond dissociation energy (BDE) for c-CN2BrMINUS SIGN 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/CF2XMINUS SIGN /CF2) exhibits similar dissociative behavior.
All experimental BDEs are in very good agreement with MP4/aug-cc-pVTZ calculations.