Production of gas-phase radical anions by reaction of O–˙ ions with organic substrates

Abstract

O^–· ions were generated from N₂O by electron impact and allowed to react with aliphatic compounds which were either unsaturated or contained an electronegative substituent. The major ionic products are OH^–, (M – H)^–, (M – H₂)^–· and (M – H + O)^– and evidence is presented which shows that the radical anions, (M – H₂)^–·, are formed by the abstraction of H⁺₂ from an activated carbon atom. The ions CH₂C^–· and CF^–₂· react with N₂O to form CH₂CN^– and CF₂N^– ions respectively, but the majority of the radical anions react at higher pressures of organic substrate to form neutral species and free electrons. This was demonstrated in the acetonitrile system by the use of double electron ejection. Other added gases tend to stabilise the radical anions rather than lead to their loss in an electron detachment process.