TY - JOUR
T1 - Generation of arylnitrenium ions by nitro-reduction and gas-phase synthesis of N-heterocycles
AU - Chen, Hao
AU - Chen, Huanwen
AU - Cooks, R. Graham
AU - Bagheri, Habib
N1 - Funding Information:
This work was supported by the National Science Foundation (CHE327190), the Office of Naval Research (N00014-02-1-0975), the Integrated Detection of Hazardous Materials (IDHM) Program, Center for Sensing Science and Technology (Purdue University), and the Naval Surface Warfare Center (Crane, Indiana).
PY - 2004/11
Y1 - 2004/11
N2 - Nitro-reduction by the vinyl halide radical cation CH 2 = CH-X +· (X = Cl or Br) converts nitroaromatics into arylnitrenium ions, significant intermediates in carcinogenesis, and the present study reports on the scope and regioselectivity of this versatile reaction. The reaction is general for different kinds of substituted nitroaromatics; para/meta substitutents have little effect on the reaction while ortho substitutents result in low yields of arylnitrenium ions. The phenylnitrenium ion PhNH + can be generated by chemical ionization (CI) of nitrobenzene using 1,2-dichloroethane as the reagent gas or by atmospheric pressure chemical ionization (APCI) of 1,2-dichloroethane solution doped with nitrobenzene. The chemical reactivities of the arylnitrenium ions include one-step ion/molecule reactions with nucleophiles ethyl vinyl ether and 1,3-dioxolanes, respectively, involving the direct formation of new CN bonds and synthesis of indole and benzomorpholine derivatives. The indole formation reaction parallels known condensed phase chemistry, while the concise morpholine-forming reaction remains to be sought in solution. The combination of collision-induced dissociation (CID) with novel ion/molecule reactions should provide a selective method for the detection of explosives such as TNT, RDX and HMX in mixtures using mass spectrometry. In addition to the reduction of the nitro group, reduction of methyl phenyl sulfone PhS(O) 2Me to the thioanisole radical cation PhSMe +· occurs using the same chemical ionization reagent 1,2-dichloroethane. This probably involves an analogous reduction reaction by the reagent ion CH 2 = CH-Cl +·.
AB - Nitro-reduction by the vinyl halide radical cation CH 2 = CH-X +· (X = Cl or Br) converts nitroaromatics into arylnitrenium ions, significant intermediates in carcinogenesis, and the present study reports on the scope and regioselectivity of this versatile reaction. The reaction is general for different kinds of substituted nitroaromatics; para/meta substitutents have little effect on the reaction while ortho substitutents result in low yields of arylnitrenium ions. The phenylnitrenium ion PhNH + can be generated by chemical ionization (CI) of nitrobenzene using 1,2-dichloroethane as the reagent gas or by atmospheric pressure chemical ionization (APCI) of 1,2-dichloroethane solution doped with nitrobenzene. The chemical reactivities of the arylnitrenium ions include one-step ion/molecule reactions with nucleophiles ethyl vinyl ether and 1,3-dioxolanes, respectively, involving the direct formation of new CN bonds and synthesis of indole and benzomorpholine derivatives. The indole formation reaction parallels known condensed phase chemistry, while the concise morpholine-forming reaction remains to be sought in solution. The combination of collision-induced dissociation (CID) with novel ion/molecule reactions should provide a selective method for the detection of explosives such as TNT, RDX and HMX in mixtures using mass spectrometry. In addition to the reduction of the nitro group, reduction of methyl phenyl sulfone PhS(O) 2Me to the thioanisole radical cation PhSMe +· occurs using the same chemical ionization reagent 1,2-dichloroethane. This probably involves an analogous reduction reaction by the reagent ion CH 2 = CH-Cl +·.
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U2 - 10.1016/j.jasms.2004.07.019
DO - 10.1016/j.jasms.2004.07.019
M3 - Article
C2 - 15519236
AN - SCOPUS:7244229730
SN - 1044-0305
VL - 15
SP - 1675
EP - 1688
JO - Journal of the American Society for Mass Spectrometry
JF - Journal of the American Society for Mass Spectrometry
IS - 11
ER -