通过质子合电子转移实现的硫胺基与基的反选择性胺化
Casey B Roos1, Joachim Demaerel1, David E Graff1
1Department of Chemistry, Princeton University, Princeton, New Jersey 08544, United States.
Journal of the American Chemical Society
|March 18, 2020
概括
这项研究引入了使用激素化学的分子内胺化方法. 它利用非共价相互作用在C-N键形成中的不对称诱导,实现高立体选择性.
科学领域:
- 有机化学
- 不对称的合成
- 激进化学
背景情况:
- 的分子内胺化是有机合成中的关键转化.
- 开发这种反应的酶选择性方法仍然是一个重大挑战.
- 基于激进的方法为传统的离子方法提供了替代途径.
研究的目的:
- 报告一种基于基的新型酶选择性方法,用于用硫胺基对基进行分子内胺化.
- 阐明涉及N中心基和质子合电子转移 (PCET) 的机制.
- 证明非对应相互作用在实现不对称诱导中的作用.
主要方法:
- 使用质子合电子转移 (PCET) 来激活硫胺N-H键.
- 采用酸以调解与短暂的N中心基的非对应相互作用.
- 研究C-N键形成阶段的立体化学结果.
主要成果:
- 通过硫胺来实现基的反选择性分子内胺化.
- 已证明具有高选择性,高达98:2er (反体比).
- 提供了非对应相互作用在不对称诱导中的作用的证据.
结论:
- 开发的方法提供了一个有效的C-N结合形成途径.
- 基质催化剂和基质中间体之间的非共价相互作用可以有效控制立体选择性.
- 这项工作扩大了基于根的不对称合成的范围.
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