title: Interception of the radicals produced in electrophilic fluorination with radical traps (Tempo, Dmpo) studied by electrospray ionization mass spectrometry.
abstract: The interaction of the nitroxide radical traps (Tempo and Dmpo) and radicals produced in the electrophilic fluorination of olefins (styrene and alpha-methylstyrene) and Selectfluor (1-chloromethyl-4-fluoro-1,4-diazoniabicyclo[2.2.2]octanebis(tetrafluoroborate) (F-TEDA-BF(4)) (1)) was investigated by electrospray ionization mass spectrometry (ESI-MS). Tempo succeeded in intercepting the radical cationic intermediates and the radical adduct ions were detected at m/z 260 (for styrene) and m/z 274 (for alpha-methylstyrene). Dmpo could also intercept the fluorine radical and radical adduct ions were detected at m/z 131, 132 and 152. The interception of the radical cationic intermediates and fluorine radical is good evidence for the presence of a single-electron transfer mechanism in the electrophilic fluorination.
authors.affiliation: Shanghai Mass Spectrometry Center, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, Shanghai 200032, China.
authors.forename: Xiang
authors.initials: X
authors.lastname: Zhang
authors.forename: Haoyang
authors.initials: H
authors.lastname: Wang
authors.forename: Yinlong
authors.initials: Y
authors.lastname: Guo
mesh_terms: D005461:Fluorine / Q000737:chemistry*; D016166:Free Radical Scavengers / Q000737:chemistry*; D005609:Free Radicals / Q000737:chemistry*; D006845:Hydrocarbons, Fluorinated / Q000737:chemistry; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*; D019097:Spin Trapping / Q000379:methods; D020058:Styrene / Q000737:chemistry; D013343:Styrenes / Q000737:chemistry
chemical_list: D016166:Free Radical Scavengers; D005609:Free Radicals; D006845:Hydrocarbons, Fluorinated; D013343:Styrenes; C027142:vinyltoluene; D005461:Fluorine; D020058:Styrene