Aminolysis of acid anhydrides in water. II. Nonlinear structure-reactivity relations in the aminolyses of phthalic and succinic anhydrides
Aminolysis of acid anhydrides in water. II. Nonlinear structure-reactivity relations in the aminolyses of phthalic and succinic anhydrides
复制标题
酸酐在水中的氨解。
DOI：
10.1021/ja00778a035
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发表时间：
1972
期刊：
影响因子：
--
通讯作者：
K. Uekama
中科院分区：
文献类型：
--
作者：
W. E. Hall;T. Higuchi;I. H. Pitman;K. Uekama
研究了21种伯胺和仲胺在水中与邻苯二甲酸酐和丁二酸酐的反应。在酸酐和胺中性分子浓度下，每个反应都是一级反应，产物分析表明胺并没有显着催化酸酐的水解反应。胺解速率常数对胺阳离子的pAfa值的曲线图不是线性的，并且显示与弱碱性胺的反应比与强碱的反应对胺的碱性更敏感。结果表明，相当数量的NC键的形成已经发生在与弱碱性胺的反应的速率决定过渡态和非常小的速率促进所带来的反应物之间的疏水键合或在过渡态。这种行为与本系列第一部分讨论的强碱性胺所表现出的结构-反应性关系形成了鲜明的对比。在本系列第一部分中，研究表明，强碱性仲胺对邻苯二甲酸酯的氨解速率对胺的碱性相对不敏感，但受胺的疏水性和空间位阻性质的显著影响。本研究是这项工作的延伸，并进行了确定这些因素对弱碱性伯胺和仲胺的邻苯二甲酸酐和琥珀酸酐的氨解的影响。
The reactions in water of 21 primary and secondary amines with phthalic and succinic anhydrides were examined. Each reaction was first order in both anhydride and amine neutral molecule concentrations, and product analysis showed that the amines did not significantly catalyze the hydrolysis reactions of the anhydrides. Plots of the logarithms of the aminolysis rate constants against the pAfa values of the amine cations were not linear and revealed that the reactions with weaklybasic amines were considerably more sensitive to the basicity of the amine than were the reactions with the strong bases. The results suggest that a considerable amount of NC bond formation has occurred in the rate-determining transition state for reactions with the weakly basic amines and that very little rate facilitation is brought about by hydrophobic bonding between reactants or in the transition state. This behavior thus contrasts markedly with the structure-reactivity relationships exhibited by strongly basic amines which were discussed in part I of this series.In part I1 of this series, it was shown that the rates of aminolysis of phthalic anhydrideby strongly basic secondary amines were relatively insensitive to the basicity of the amine but were significantly influenced by the hydrophobic and steric properties of the amine. The present study is an extension of this work and was undertaken to ascertain the influence of these factors on the aminolyses of phthalic and succinic anhydrides by weakly basic primary and secondary amines.