title: Generation of gas-phase sodiated arenes such as [(Na3(C6H4)+] from benzene dicarboxylate salts.
abstract: Upon collision-induced activation, gaseous sodium adducts generated by electrospray ionization of disodium salts of 1,2- 1,3-, and 1,4-benzene dicarboxylic acids (m/z 233) undergo an unprecedented expulsion of CO(2) by a rearrangement process to produce an ion of m/z 189 in which all three sodium atoms are retained. When isolated in a collision cell of a tandem-in-space mass spectrometer, and subjected to collision-induced dissociation (CID), only the m/z 189 ions derived from the meta and para isomers underwent a further CO(2) loss to produce a peak at m/z 145 for a sodiated arene of formula (Na(3)C(6)H(4))(+). This previously unreported m/z 145 ion, which is useful to differentiate meta and para benzene dicarboxylates from their ortho isomer, is in fact the sodium adduct of phenelenedisodium. Moreover, the m/z 189 ion from all three isomers readily expelled a sodium radical to produce a peak at m/z 166 for a radical cation [(*C(6)H(4)CO(2)Na(2))(+)], which then eliminated CO(2) to produce a peak at m/z 122 for the distonic cation (*C(6)H(4)Na(2))(+).
authors.affiliation: Center for Mass Spectrometry, Department of Chemistry and Chemical Biology, Stevens Institute of Technology, Hoboken, NJ 07030, USA. athula.attygalle@stevens.edu
authors.forename: Athula B
authors.initials: AB
authors.lastname: Attygalle
authors.forename: Chang-Ching
authors.initials: CC
authors.lastname: Chan
authors.forename: Frank U
authors.initials: FU
authors.lastname: Axe
authors.forename: Mark
authors.initials: M
authors.lastname: Bolgar
mesh_terms: D001554:Benzene / Q000737:chemistry*; D003998:Dicarboxylic Acids / Q000737:chemistry*; D007536:Isomerism; D010795:Phthalic Acids / Q000737:chemistry; D012492:Salts / Q000737:chemistry; D012964:Sodium / Q000737:chemistry*; D020160:Sodium Benzoate / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D053719:Tandem Mass Spectrometry / Q000379:methods*
chemical_list: D003998:Dicarboxylic Acids; D010795:Phthalic Acids; D012492:Salts; C059768:isophthalate; D012964:Sodium; D001554:Benzene; D020160:Sodium Benzoate