Lehrstuhl für Physikalische Chemie II, Universität Erlangen-Nürnberg, Egerlandstraße 3, 91058 Erlangen, Germany.
Chemphyschem. 2012 May 14;13(7):1725-35. doi: 10.1002/cphc.201100965. Epub 2012 Mar 1.
We demonstrate the application of in situ X-ray photoelectron spectroscopy (XPS) to monitor organic, liquid-phase reactions. By covalently attaching ionic head groups to the reacting organic molecules, their volatility can be reduced such that they withstand ultra high vacuum conditions. The applied method, which is new for the investigation of organic reactions, allows for following the fate of all elements present in the reaction mixture--except for hydrogen--in a quantitative and oxidation-state-sensitive manner in one experiment. This concept is demonstrated for the alkylation of a tertiary amine attached to an imidazolium or phosphonium moiety by the anion 4-chlorobutylsulfonate (ClC(4)H(8)SO(3)). In the course of the reaction, the covalently bound chlorine is converted to chloride and the amine to ammonium as reflected by the distinct shifts in the N 1s and Cl 2p binding energies.
我们展示了原位 X 射线光电子能谱（XPS）在监测有机液相反应中的应用。通过将离子头基共价连接到反应的有机分子上，可以降低它们的挥发性，从而使它们能够承受超高真空条件。这种应用方法，对于有机反应的研究来说是新颖的，允许在一个实验中以定量和氧化态敏感的方式跟踪反应混合物中除氢以外的所有元素的命运。这个概念通过将叔胺连接到咪唑鎓或鏻部分上的烷基化反应来证明，该反应由阴离子 4-氯丁基磺酸盐(ClC(4)H(8)SO(3))引发。在反应过程中，共价结合的氯被转化为氯离子，胺被转化为铵离子，这反映在 N 1s 和 Cl 2p 结合能的明显位移上。
