浙江大学史炳锋团队取报道了电氧化铑（III）/手性羧酸催化磺酰亚胺与炔烃的对映选择性C-H环化反应。相关研究成果于2024年1月30日发表在国际知名学术期刊《德国应用化学》。

非手性Cp*Rh（III）与手性羧酸（CCAs）的组合代表了，过渡金属催化的对映选择性C–H活化的有效催化体系。然而，这种混合催化仅限于氧化还原中性C-H活化反应，而采用氧化对映选择性C-H活化仍然难以捉摸，并构成了重大挑战。

该文中，研究人员描述了在室温下，在操作友好的未分割电池中，通过手性羧酸（CCA）实现的电化学Cp*Rh（III）催化的磺酰亚胺，与炔烃的对映选择性CH环化的发展。以高产率获得了广泛的对映体富集的1,2-苯并噻嗪，且具有优异的对映选择性（高达99%的产率和98:2er）。在外循环间歇式反应器中通过放大反应证明了该方法的实用性。研究人员分离、表征和转化了一种关键的手性Cp*Rh（III）中间体，为Rh（Ⅲ）/Rh（Ⅰ）电催化循环提供了合理的支持。

附：英文原文

Title: Electrooxidative Rhodium(III)/Chiral Carboxylic Acid-Catalyzed Enantioselective C?H Annulation of Sulfoximines with Alkynes

Author: Gang Zhou, Tao Zhou, Ao-Lian Jiang, Pu-Fan Qian, Jun-Yi Li, Bo-Yang Jiang, Zi-Jia Chen, Bing-Feng Shi

Issue&Volume: 2024-01-30

Abstract: The combination of achiral Cp*Rh(III) with chiral carboxylic acids (CCAs) represents an efficient catalytic system in transition metal-catalyzed enantioselective C–H activation. However, this hybrid catalysis is limited to redox-neutral C-H activation reactions and the adopt to oxidative enantioselective C–H activation remains elusive and pose a significant challenge. Herein, we describe the development of an electrochemical Cp*Rh(III)-catalyzed enantioselective CH annulation of sulfoximines with alkynes enabled by chiral carboxylic acid (CCA) in an operationally friendly undivided cell at room temperature. A broad range of enantioenriched 1,2-benzothiazines were obtained in high yields with excellent enantioselectivities (up to 99% yield and 98:2 er). The practicality of this method was demonstrated by scale-up reaction in a batch reactor with external circulation. A crucial chiral Cp*Rh(III) intermediate was isolated, characterized, and transformed, providing rational support for a Rh(III)/Rh(I) electrocatalytic cycle.

DOI: 10.1002/anie.202319871

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202319871