Nonclassical ammonium ions as intermediates in cinchona alkaloid rearrangements?
Nonclassical ammonium ions as intermediates in cinchona alkaloid rearrangements?
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DOI：
10.1002/chir.23188
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发表时间：
2020-02-14
期刊：
影响因子：
2
通讯作者：
Tantillo, Dean J.
中科院分区：
文献类型：
--
作者：
Lodewyk, Michael W.;Tantillo, Dean J.
研究了可能参与金鸡纳生物碱溶解及相关反应的阳离子铵中间体的经典/非经典性质。虽然这些中间体被发现具有高度扭曲的几何结构，其中中心氮原子和三个连接的基团基本上是共面的，但我们没有发现非经典成键阵列的证据。相反，我们发现有证据表明，中间体类似于经典的氮杂环丙烷结构，尽管是应变的，这仍然能够解释实验观察。
The classical/nonclassical nature of cationic ammonium intermediates proposed to be involved in cinchona alkaloid solvolysis and related reactions is investigated. While these intermediates are found to possess highly distorted geometries in which the central nitrogen atom and three of the attached groups are essentially coplanar, we do not find evidence of a nonclassical bonding array. Instead, we find evidence that the intermediate resembles a classical, albeit strained, aziridinium structure, which is still able to account for experimental observations.