title: Gas-phase carbene radical anions: new mechanistic insights.
abstract: The gas-phase reactivity of the CHCl*- anion has been investigated with a series of halomethanes (CCl4, CHCl3, CH2Cl2, and CH3Cl) using a FA-SIFT instrument. Results show that this anion primarily reacts via substitution and by proton transfer. In addition, the reactions of CHCl*- with CHCl3 and CH2Cl2 form minor amounts of Cl2*- and Cl-. The isotopic distribution of these two products is consistent with an insertion-elimination mechanism, where the anion inserts into a C-Cl bond to form an unstable intermediate, which eliminates either Cl2*- or Cl- and Cl*. Neutral and cationic carbenes are known to insert into single bonds; however, this is the first observation of such reactivity for carbene anions.
authors.affiliation: JILA, University of Colorado and the National Institute of Standards and Technology and the University of Colorado, Department of Chemistry and Biochemistry, 215 UCB, Boulder, Colorado 80309-0215, USA.
authors.forename: Stephanie M
authors.initials: SM
authors.lastname: Villano
authors.forename: Nicole
authors.initials: N
authors.lastname: Eyet
authors.forename: W Carl
authors.initials: WC
authors.lastname: Lineberger
authors.forename: Veronica M
authors.initials: VM
authors.lastname: Bierbaum
mesh_terms: D000838:Anions / Q000737:chemistry; D005740:Gases; D006843:Hydrocarbons, Chlorinated / Q000737:chemistry*; D007700:Kinetics; D008697:Methane / Q000031:analogs & derivatives* / Q000737:chemistry; D013816:Thermodynamics
chemical_list: D000838:Anions; D005740:Gases; D006843:Hydrocarbons, Chlorinated; C030011:carbene; D008697:Methane