title: Charge-tagged N-heterocyclic carbenes (NHC): Direct transfer from ionic liquid solutions and long-lived nature in the gas phase.
abstract: Negatively charge-tagged N-heterocyclic carbenes have been formed in solution via deprotonation of imidazolium ions bearing acid side groups and transferred to the gas phase via ESI(-)-MS. The structure of the putative and apparently stable gaseous carbenes formed in such conditions were then probed via reactions with carbon dioxide using a triple quadrupole mass spectrometer particularly optimized for ion/molecule reactions of ESI-generated ions. Complete conversion to imidazolium carboxylates was achieved, which seems to demonstrate the efficiency of the transfer, the gas-phase stability, and the long-lived nature of these unprecedented charge-tagged carbenes and their predominance in the ionic population. Comprehensive studies on the intrinsic reactivity of N-heterocyclic carbenes with silent charge tags are therefore possible. Graphical Abstract ᅟ.
authors.affiliation: Laboratory of Medicinal and Technological Chemistry, University of Brasília (IQ-UnB), Campus Universitário Darcy Ribeiro, CEP 70904970, P.O.Box 4478, Brasília, DF, Brazil.
authors.forename: Thyago S
authors.initials: TS
authors.lastname: Rodrigues
authors.affiliation: Institut Parisien de Chimie Moléculaire, UMR 8232, Université Pierre et Marie Curie-Paris6, 4 place Jussieu, 75252, Paris Cedex 05, France.
authors.forename: Denis
authors.initials: D
authors.lastname: Lesage
authors.affiliation: Laboratory of Medicinal and Technological Chemistry, University of Brasília (IQ-UnB), Campus Universitário Darcy Ribeiro, CEP 70904970, P.O.Box 4478, Brasília, DF, Brazil.
authors.forename: Wender A
authors.initials: WA
authors.lastname: da Silva
authors.affiliation: Institut Parisien de Chimie Moléculaire, UMR 8232, Université Pierre et Marie Curie-Paris6, 4 place Jussieu, 75252, Paris Cedex 05, France.
authors.forename: Richard B
authors.initials: RB
authors.lastname: Cole
authors.affiliation: Laboratory of Molecular Catalysis, Institute of Chemistry, UFRGS, Av. Bento Gonçalves, 9500, Porto Alegre, 91501-970, RS, Brazil.
authors.forename: Günter
authors.initials: G
authors.lastname: Ebeling
authors.affiliation: Laboratory of Molecular Catalysis, Institute of Chemistry, UFRGS, Av. Bento Gonçalves, 9500, Porto Alegre, 91501-970, RS, Brazil.
authors.forename: Jaïrton
authors.initials: J
authors.lastname: Dupont
authors.affiliation: Laboratory of Medicinal and Technological Chemistry, University of Brasília (IQ-UnB), Campus Universitário Darcy Ribeiro, CEP 70904970, P.O.Box 4478, Brasília, DF, Brazil.
authors.forename: Heibbe C B
authors.initials: HCB
authors.lastname: de Oliveira
authors.affiliation: Thomson Mass Spectrometry Laboratory, University of Campinas-UNICAMP, Campinas, SP, Brazil. eberlin@iqm.unicamp.br.
authors.forename: Marcos N
authors.initials: MN
authors.lastname: Eberlin
authors.affiliation: Laboratory of Medicinal and Technological Chemistry, University of Brasília (IQ-UnB), Campus Universitário Darcy Ribeiro, CEP 70904970, P.O.Box 4478, Brasília, DF, Brazil. brenno.ipi@gmail.com.
authors.forename: Brenno A D
authors.initials: BAD
authors.lastname: Neto
keywords: Ion/molecule reactions; Ionic liquids; N-heterocyclic carbenes