Institut für Physikalische und Theoretische Chemie, Universität Würzburg, Am Hubland, 97074, Würzburg, Germany.
Present address: Institut des Sciences Moléculaires d'Orsay ISMO (UMR 8214 CNRS), Bâtiment 350, Université Paris-Saclay, 91405, Orsay Cedex, France.
Angew Chem Int Ed Engl. 2017 Jun 26;56(27):8000-8003. doi: 10.1002/anie.201703433. Epub 2017 Jun 6.
Nitrogen-containing resonance-stabilized radicals such as the picolyl radical are important in combustion chemistry and astrochemistry. They have only been scarcely studied because an isomer-selective generation is often difficult. Herein, we present threshold photoelectron spectra of the three picolyl radical isomers, C H N, that were obtained with synchrotron radiation. The radicals were selectively generated by flash pyrolysis from aminomethylpyridine precursors through deamination. Ionization energies of 7.70, 7.59, and 8.01 eV were determined for 2-, 3-, and 4-picolyl, respectively. The observed vibrational structure was assigned to an in-plane deformation mode of the aromatic ring. The spectroscopic insight gained in this study can be used to distinguish different picolyl isomers in on-line combustion analysis, for example.
含氮共振稳定自由基，如吡啶基自由基，在燃烧化学和天体化学中非常重要。由于异构体选择性生成通常很困难，因此它们的研究很少。在此，我们使用同步辐射获得了三种吡啶基自由基异构体 C6H6NNH2（C6H5CH2NH2）的阈光电离能谱。自由基通过氨甲吡啶前体的闪蒸热解通过脱氨选择性生成。分别确定 2-、3-和 4-吡啶基自由基的电离能为 7.70、7.59 和 8.01eV。观察到的振动结构被分配到芳香环的面内变形模式。本研究中获得的光谱见解可用于在线燃烧分析中区分不同的吡啶基异构体，例如。
