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The mechanisms of hydride exchange, organic combination and displacement reactions.

机译：氢化物交换，有机结合和置换反应的机理。

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The primary aim of this dissertation was to seek the answer to the question: "Is the single transition-state model appropriate for the fundamental reactions in organic chemistry?" The goal was accomplished by performing enormous kinetic data collection and detailed mechanistic analysis on several typical fundamental organic chemical reactions.;Three new methodologies for differentiating between a simple one-step and complex multi-step mechanism were developed and extensively confirmed during the application in the kinetic studies of all of the reaction discussed in this dissertation. The three methods consist of (1) half-life dependence of kapp, (2) sequential linear pseudo-first-order correlation, and (3) revised instantaneous rate constant analysis.;A detailed kinetic investigation of the formal hydride transfer reaction of NADH models [N-benzyl-1,4-dihydronicotinamide (BNAH) with N-methylacridinium (MA+) and N-methyl-9,10-dihydroacridine (MAH) with tropylium ion (Tr+)] confirmed that both these reactions take place in more than one step and involve kinetically significant reactant complex intermediates, which are noncovalentlly bound intermediates. Computations at the M06-2x/6-311++G(d,p) level provided the structure of the reactant complex intermediate. A reinvestigation of the formal hydride transfer reaction of 1-benzyl-3-cyanoquinolinium ion (BQCN+) with N-methyl-9,10-dihydroacridine (MAH) in acetonitrile (AN) confirmed that the reaction takes place in more than one step and revealed a new mechanism that had not previously been considered. It was observed that even residual oxygen under glove box conditions initiates a chain process leading to the same products.;The combination reactions studied include the reaction between a carbocation and an anion as well as the reaction of trans-beta-nitrostyrene with nitroethide ion. Conventional pseudo-first-order analysis as well as instantaneous rate constant analysis confirmed that the combination reactions do not follow the simple one-step mechanism. The SN2 displacement of halide ions by the 4-nitrophenoxide ion was also investigated and the kinetic data are inconsistent with the concerted single transition-state model.
机译：本文的主要目的是寻找以下问题的答案：“单一过渡态模型是否适合有机化学中的基本反应？”该目标是通过对几种典型的基本有机化学反应进行大量的动力学数据收集和详细的机理分析来实现的。;三种区分简单的一步法和复杂的多步机理的新方法得到了开发，并在应用中得到了广泛的证实。本文讨论的所有反应的动力学研究。这三种方法包括（1）kapp的半衰期依赖性，（2）顺序线性拟一阶相关性和（3）修正的瞬时速率常数分析。; NADH形式氢化物转移反应的详细动力学研究模型[带有N-甲基-1啶鎓（MA +）的N-苄基-1,4-二氢烟酰胺（BNAH）和带有对ion离子（Tr +）的N-甲基-9,10-二氢ac啶（MAH）的模型证实了这两种反应都是在一步，涉及动力学上重要的反应物配合物中间体，它们是非共价键结合的中间体。 M06-2x / 6-311 ++ G（d，p）级的计算提供了反应物中间体的结构。对1-苄基-3-氰基喹啉鎓离子（BQCN +）与N-甲基-9,10-二氢ac啶（MAH）在乙腈（AN）中的正式氢化物转移反应的再研究证实了该反应是在一个以上的步骤中进行的揭示了以前没有考虑过的新机制。观察到，即使在手套箱条件下残留氧气也会引发形成相同产物的链过程。研究的组合反应包括碳正离子与阴离子之间的反应以及反式-β-硝基苯乙烯与硝基乙离子的反应。常规的伪一阶分析以及瞬时速率常数分析证实了组合反应不遵循简单的一步机制。还研究了4-硝基苯氧离子对SN2取代卤离子的影响，动力学数据与协调的单过渡态模型不一致。

著录项

  • 作者

    Hao, Weifang.;

  • 作者单位

    Utah State University.;

  • 授予单位 Utah State University.;
  • 学科 Chemistry Organic.
  • 学位 Ph.D.
  • 年度 2012
  • 页码 249 p.
  • 总页数 249
  • 原文格式 PDF
  • 正文语种 eng
  • 中图分类
  • 关键词

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