Wu Lianqian, Zhang Zhihan, Wu Dunqi, Wang Fei, Chen Pinhong, Lin Zhenyang, Liu Guosheng
State Key Laboratory of Organometallic Chemistry, Shanghai Hong Kong Joint Laboratory in Chemical Synthesis, Center for Excellence in Molecular Synthesis, Shanghai Institute of Organic Chemistry, University of Chinese Academy of Sciences, Chinese Academy of Sciences, 345 Lingling Road, Shanghai, 200032, China.
Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong, China.
Angew Chem Int Ed Engl. 2021 Mar 22;60(13):6997-7001. doi: 10.1002/anie.202015083. Epub 2021 Feb 17.
Asymmetric radical azidation for the synthesis of chiral alkylazides remains a tremendous challenge in organic synthesis. We report here an unprecedented highly enantioselective radical azidation of acrylamides catalyzed by 1 mol % of a copper catalyst. The substrates were converted to the corresponding alkylazides in high yield with good-to-excellent enantioselectivity. Notably, employing an anionic cyano-bisoxazoline (CN-Box) ligand is crucial to generate a monomeric Cu azide species, rather than a dimeric Cu azide intermediate, for this highly enantioselective radical azidation.
用于合成手性烷基叠氮化物的不对称自由基叠氮化反应在有机合成中仍然是一个巨大的挑战。我们在此报告了一种前所未有的由1 mol%的铜催化剂催化的丙烯酰胺的高对映选择性自由基叠氮化反应。底物以高产率转化为相应的烷基叠氮化物,对映选择性良好至优异。值得注意的是,对于这种高对映选择性自由基叠氮化反应,使用阴离子氰基双恶唑啉(CN-Box)配体对于生成单体铜叠氮化物物种而非二聚体铜叠氮化物中间体至关重要。