Ion-mediated amination of hydrocarbons in the gas phase

FeNH+ is chosen as a model system to probe the transition-metal-mediated tr ansfer of imine groups in the gas phase by mass-spectrometric means. Ab ini tio calculations at the MR-ACPF level predict FeNH+ to have a Linear sextet ground state ((6)Sigma(+)); a bent quartet state ((4)A') and a linear doub let state ((2)Delta) are higher in energy by 0.14 eV and 0.51 eV, respectiv ely The bond-dissociation energy is determined to D(Fe+ - NH) = 69 +/- 2 kc al mol(-1) using ion-molecule reactions. Charge-stripping experiments combi ned with ab initio calculations yield an ionization energy of IE(FeNH+) = 1 5.7 +/- 0.5 eV. The chemical behavior of FeNH+ towards oxygen, water, hydro gen, aliphatic hydrocarbons, benzene, and toluene reveals an intrinsically high reactivity of FeNH+. Because a transfer of the (NH) fragment to the su bstrate is feasible in most cases, attractive amination reactions like meth ane --> methylamine, benzene --> aniline, or toluene - benzylidenamine can be afforded by FeNH+.