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通过使用 photoredox 催化剂进行单向和异步 PCET 的化学选择性键激活

Rui Sun¹, Serge Ruccolo¹, Daniel L Nascimento¹

¹Department of Chemistry and Chemical Biology, Harvard University 12 Oxford Street Cambridge MA 02138 USA dnocera@fas.harvard.edu.

Chemical science

|December 11, 2023

概括

子通过质子联电子转移 (PCET) 从胺N-H键中选择性地抽取原子,使分子内基胺化能够使用可持续的光催化剂形成乳酸盐.

科学领域:

有机化学有机化学
光催化作用的光催化
反应机制反应机制

背景情况:

三倍激发状态是已知的反应中间体.
质子合电子转移 (PCET) 是许多化学反应中的一个关键机制.
在有机合成中,C-H和N-H键的选择性功能化仍然是一个挑战.

研究的目的:

为了研究从胺N-H键中通过子三重体状态选择性原子抽象.
阐明电离能 (IE) 和键解离能 (BDE) 在化学选择性中的作用.
开发一种用于分子内抗马尔科夫尼科夫分子胺化的光催化方法.

主要方法:

使用坎福基作为可持续的光催化剂.
研究了质子合电子转移 (PCET) 的机制.
分析了基于IE和BDE的原子抽象的选择性.

主要成果:

从强胺 N-H 键中实现了选择性 H 原子抽象,而不是较弱的 C-H 键.
证明化学选择性源于PCET中的异步电子和质子转移.
通过基的分子内抗马尔科夫尼科夫胺化成功合成了乳酸盐.

结论:

PCET途径使选择性N-H键功能化成为可能.
IE差异,而不是BDE,驱动观察到的化学选择性.
坎佛诺是乳糖合成的有效和可持续的光催化剂.

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