Yang Fuxing, Chi Longxiao, Ye Ziqi, Gong Lei
Key Laboratory of Chemical Biology of Fujian Province, iChEM, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen, Fujian 361005, China.
School of Chemistry and Chemical Engineering, Henan Normal University, Xinxiang, Henan 453007, China.
J Am Chem Soc. 2025 Jan 15;147(2):1767-1780. doi: 10.1021/jacs.4c13321. Epub 2025 Jan 2.
Regiodivergent asymmetric synthesis represents a transformative strategy for the efficient generation of structurally diverse chiral products from a single set of starting materials, significantly enriching their enantiomeric composition. However, the design of radical-mediated regiodivergent and enantioselective reactions that can accommodate a wide range of functional groups and substrates has posed significant challenges. The obstacles primarily lie in switching the regioselectivity and achieving high enantiodiscrimination, especially when dealing with high-energy intermediates. To address these issues, we have developed a new catalytic system that integrates photoinduced hydrogen atom transfer (HAT) and chiral copper catalysis, involving the fine-tuning of chiral ligands, additives, and other reaction parameters. The strategy facilitates regiodivergent and enantioselective cross-couplings between -aryl glycine ester/amide derivatives and abundant hydrocarbon feedstocks through strong C(sp)-H bond activation. This approach allows for the controlled and stereoselective formation of C(sp)-C(sp) and C(sp)-N bonds, yielding a rich variety of C- or N-alkylated glycine esters and amides with commendable yields (up to 92% yield), exclusive regioselectivities (typically >20:1 rr), and high enantioselectivities (up to 96% ee). Our methodology not only provides a promising avenue for the stereoselective incorporation of alkyl functionalities onto specific sites of biologically significant molecules but also offers a practical approach for regioselectivity switching while simultaneously achieving high asymmetric induction within photochemical reactions.
区域发散不对称合成是一种变革性策略,可从单一组起始原料高效生成结构多样的手性产物,显著丰富其对映体组成。然而,设计能够容纳广泛官能团和底物的自由基介导的区域发散和对映选择性反应面临重大挑战。这些障碍主要在于切换区域选择性和实现高对映体区分,特别是在处理高能中间体时。为了解决这些问题,我们开发了一种新的催化体系,该体系整合了光致氢原子转移(HAT)和手性铜催化,涉及对手性配体、添加剂和其他反应参数的微调。该策略通过强大的C(sp)-H键活化促进了 -芳基甘氨酸酯/酰胺衍生物与丰富的烃类原料之间的区域发散和对映选择性交叉偶联。这种方法允许可控且立体选择性地形成C(sp)-C(sp)和C(sp)-N键,以可观的产率(高达92%产率)、独特的区域选择性(通常>20:1 rr)和高对映选择性(高达96% ee)生成多种C-或N-烷基化甘氨酸酯和酰胺。我们的方法不仅为将烷基官能团立体选择性地引入具有生物学意义的分子的特定位点提供了一条有前景的途径,而且还为区域选择性切换提供了一种实用方法,同时在光化学反应中实现高不对称诱导。