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首页> 外文学位 >PART I. ANALYTICAL APPLICATIONS OF MASS SPECTROMETRY/MASS SPECTROMETRY (MS/MS). PART II. INVESTIGATIONS OF ION-MOLECULE REACTIONS PRODUCTS BY MS/MS. PART III. THE QUESTION OF TAUTOMERISM OF ALKYLNITRILE AND ISONITRILE RADICAL CATIONS.
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PART I. ANALYTICAL APPLICATIONS OF MASS SPECTROMETRY/MASS SPECTROMETRY (MS/MS). PART II. INVESTIGATIONS OF ION-MOLECULE REACTIONS PRODUCTS BY MS/MS. PART III. THE QUESTION OF TAUTOMERISM OF ALKYLNITRILE AND ISONITRILE RADICAL CATIONS.

机译：第一部分：质谱法/质谱法（MS / MS）的分析应用。第二部分MS / MS对离子反应产物的研究。第三部分烷基和异腈基自由基的对映异构问题。

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摘要

Part I. We describe the design of a unique high resolution mass spectrometry/mass spectrometry (ms/ms) instrument having the configuration electrostatic analyzer, magnetic sector, and electrostatic analyzer (EBE). Suitable experiments are reported which evaluate the instrument in terms of the requirements for analytical ms/ms applications: high resolution mass selection, high dynamic range, and good transmission for collision-induced decomposition (CID) fragments. The unique capability of triple-sector instruments to monitor consecutive collision-induced reactions is applied to the analysis of mixtures of ions which are isobaric and isomeric, respectively. In addition, a method for the analysis of tetrachlorodibenzo-p-dioxin (TCDD) suitable for use with double or triple sector instruments is described in which the loss of COCl from the molecular ion is monitored. The precision, quality of calibration, and detection limit are evaluated directly, and the accuracy and specificity are tested by comparing the results of an analysis of soil samples with those obtained using GC/HRMS.;Part III. We use unimolecular and collision-induced dissociations to establish that the isomeric pairs {CH(,3)CN}('+) and {CH(,2)CNH}('+) and {CH(,3)NC}('+) and {CH(,2)NCH}('+) are stable, noninterconverting structures, even when activated to decompose. The same conclusion pertains to the ions {CH(,3)CH(,2)CN}('+) and {CH(,3)CHCNH}('+) and for {NCCH(,2)CH(,2)CN}('+), {NCCH(,2)CHCNH}('+), and {HNCCHCHCNH}('+). The energy barrier of a {1,3}-hydrogen shift, a possible isomerization mechanism, is determined to be at least 76 kcal mol('-1) for the {CH(,3)CN}('+) and {CH(,2)CNH}('+) pair.;Part II. We employ ms/ms techniques to study the ion-molecule reaction products created and collisionally-stabilized in a high-pressure ion source. By comparison of unimolecular and collision-induced dissociation spectra, it is demonstrated that the stabilized collision complex from the reaction of {o-quinodimethane}('+) and styrene is shown to have the structure of 2-phenyltetralin, the anticipated product of a {4+2}-cycloaddition mechanism. The stabilized complex from the reaction of {styrene}('+) and neutral styrene is shown not to have the structure of 1-phenyltetralin, and we offer evidence in favor of a formal {4+2}-cycloaddition mechanism. The stabilized complexes of {1,3-butadiene}('+) and olefins are shown not to possess the structures expected for a {4+2}-cycloaddition mechanism.
机译：第一部分，我们描述了一种独特的高分辨率质谱/质谱（ms / ms）仪器的设计，该仪器具有静电分析仪，磁性扇区和静电分析仪（EBE）的配置。报告了适当的实验，这些实验根据分析ms / ms应用的要求评估了该仪器：高分辨率质量选择，高动态范围和碰撞诱导分解（CID）碎片的良好透射率。三扇区仪器监测连续碰撞诱发反应的独特功能分别应用于等压和异构离子混合物的分析。另外，描述了一种适用于双或三段仪器的四氯二苯并-对-二恶英（TCDD）分析方法，该方法可监测分子离子中COCl的损失。直接评估精度，校准质量和检测极限，并通过将土壤样品的分析结果与使用GC / HRMS进行的分析结果进行比较来测试准确性和特异性。我们使用单分子和碰撞诱导的解离来建立异构体对{CH（，3）CN}（'+）和{CH（，2）CNH}（'+）和{CH（，3）NC}（' +）和{CH（，2）NCH}（'+）是稳定的，非互转换结构，即使被激活分解也是如此。相同的结论与离子{CH（，3）CH（，2）CN}（'+）和{CH（，3）CHCNH}（'+）有关，对于{NCCH（，2）CH（，2） CN}（'+），{NCCH（，2）CHCNH}（'+）和{HNCCHCHCNH}（'+）。对于{CH（，3）CN}（'+）和{CH}，{1,3}-氢转移的能垒（一种可能的异构化机理）被确定为至少76 kcal mol（'-1） （，2）CNH}（'+）对。第二部分。我们采用ms / ms技术研究高压离子源中产生并碰撞稳定的离子分子反应产物。通过比较单分子和碰撞诱导的解离光谱，表明由{o-quinodimethane}（'+）与苯乙烯反应形成的稳定的碰撞配合物具有2-苯基四氢萘的结构，这是α-的预期产物。 {4 + 2} -cycloaddition机制。由{苯乙烯}（'+）与中性苯乙烯反应制得的稳定络合物显示不具有1-苯基四氢萘的结构，我们提供了支持正式的{4 + 2}-环加成机理的证据。 {1,3-丁二烯}（'+）和烯烃的稳定的配合物显示不具有{4 + 2}-环加成机理所期望的结构。

著录项

  • 作者

    CHESS, EDWARD KELLEY.;

  • 作者单位

    The University of Nebraska - Lincoln.;

  • 授予单位 The University of Nebraska - Lincoln.;
  • 学科 Chemistry Analytical.
  • 学位 Ph.D.
  • 年度 1982
  • 页码 317 p.
  • 总页数 317
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

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