河南大学江智勇团队报道了顺序光氧化还原中性和手性Brønsted酸催化脱乙酰化。相关研究成果发表在2022年10月17日出版的国际知名学术期刊《德国应用化学》。

催化脱羧是一种理想的合成策略，因为它形式上完美地利用了原子。不对称光催化被认为是以经济的方式，实现这种有吸引力的反应模式的一种很有前途的工具，但它仍然不发达。

该文中，研究人员报告了一个基于光氧化还原的中性催化新平台，能够高效和模块化地光学富集α-氨基酯和其他有价值的类似物。光催化剂和底物之间的两个单电子转移过程用于提供关键的前手性中间体，手性溴化催化剂介导对映选择性质子化以重构立体生成的CH键。去乙酰化的效率由立体中心形成步骤中的对映面分化效应决定。

附：英文原文

Title: Deracemization through Sequential Photoredox-Neutral and Chiral Brønsted Acid Catalysis

Author: Ziwei Gu, Li Zhang, Haijun Li, Shanshan Cao, Yanli Yin, Xiaowei Zhao, Xu Ban, Zhiyong Jiang

Issue&Volume: 2022-10-17

Abstract: Catalytic deracemization is an ideal synthetic strategy due to its formally perfect atom utilization. Asymmetric photocatalysis has been appreciated as a promising tool to accomplish this attractive reaction pattern in an economical fashion, but it remains underdeveloped. Here, we report a new platform based on photoredox-neutral catalysis, allowing efficient and modular optical enrichment of α-amino esters and other valuable analogues. Two single-electron transfer processes between the photocatalyst and the substrates serve to provide the key prochiral intermediates, and the chiral Brnsted acid catalyst mediates enantioselective protonation to reconstitute a stereogenic CH bond. The efficiency of deracemization is determined by the enantiofacial differentiation effect during the stereocentre-forming step.

DOI: 10.1002/anie.202211241

Source: https://onlinelibrary.wiley.com/doi/10.1002/anie.202211241