当前位置:科学网首页 > 小柯机器人 >详情
电光催化解耦自由基接力反应实现高效手性选择性苄基C-H功能化
作者:小柯机器人 发布时间:2022/11/18 19:58:31

中科院上海有机所Guosheng Liu小组近日取得一项新成果。经过不懈努力,他们利用电光催化解耦自由基接力反应实现高效手性选择性苄基C-H功能化。相关论文发表在2022年11月17日出版的《美国化学会杂志》上。

在该文中,研究组通过光电催化与铜催化相结合,开发了一种高效、可持续的对映选择性苄基C-H氰化反应方法。这种新型催化体系可以通过分别调节蒽醌类光催化剂的电子性质和施加的电流,独立控制苄基自由基形成的氢原子转移步骤和Cu(II)/Cu(I)物种转化,使人们得以有效捕获瞬态自由基中间体。

研究人员表示,这种解耦自由基接力催化的方法为不同烷基芳烃的对映选择性苄基C-H氰化反应提供了统一的方法,而许多这样的反应使用已有的依赖耦合自由基接力的反应活性要低得多甚至不反应。此外,目前的方案也适用于生物活性分子,包括天然产物和药物的后期功能化。

据悉,非对称sp3 C-H功能化已经被证明可以大大加快目标分子的合成,适用范围从原料升级到复杂分子的后期修饰。

附:英文原文

Title: Electrophotocatalytic Decoupled Radical Relay Enables Highly Efficient and Enantioselective Benzylic C–H Functionalization

Author: Wenzheng Fan, Xueyao Zhao, Yunshun Deng, Pinhong Chen, Fei Wang, Guosheng Liu

Issue&Volume: November 17, 2022

Abstract: Asymmetric sp3 C–H functionalization has been demonstrated to substantially expedite target molecule synthesis, spanning from feedstocks upgradation to late-stage modification of complex molecules. Herein, we report a highly efficient and sustainable method for enantioselective benzylic C–H cyanation by merging electrophoto- and copper catalysis. A novel catalytic system allows one to independently regulate the hydrogen atom transfer step for benzylic radical formation and speciation of Cu(II)/Cu(I) to effectively capture the transient radical intermediate, through tuning the electronic property of anthraquinone-type photocatalyst and simply modulating the applied current, respectively. Such decoupled radical relay catalysis enables a unified approach for enantioselective benzylic C–H cyanation of diverse alkylarenes, many of which are much less reactive or even unreactive using the existing method relying on coupled radical relay. Moreover, the current protocol is also amenable to late-stage functionalization of bioactive molecules, including natural products and drugs.

DOI: 10.1021/jacs.2c09366

Source: https://pubs.acs.org/doi/10.1021/jacs.2c09366

 

期刊信息

JACS:《美国化学会志》,创刊于1879年。隶属于美国化学会,最新IF:14.612
官方网址:https://pubs.acs.org/journal/jacsat
投稿链接:https://acsparagonplus.acs.org/psweb/loginForm?code=1000