Flavin/I2‐Catalyzed Aerobic Oxidative C–H Sulfenylation of Aryl‐Fused Cyclic Amines

• Published in: European journal of organic chemistry Vol. 2020; no. 25; pp. 3889 - 3895
• Main Authors: Jiang, Xinpeng, Zhao, Zongchen, Shen, Zhifeng, Chen, Keda, Fang, Liyun, Yu, Chuanming
• Format: Journal Article
• Language: English
• Published: WEINHEIM Wiley 07.07.2020; Wiley Subscription Services, Inc
• Subjects: Amines; Aromatic compounds; Chemistry; Chemistry, Organic; Heterocyclic compounds; Indoles; Nitrogen heterocycles; Oxidation; Oxidizing agents; Physical Sciences; Science & Technology; Sulfenylation; Synthetic methods; Thiols; NITROGEN-HETEROCYCLES; Sulfenylation; TUBULIN POLYMERIZATION; CATALYZED REGIOSELECTIVE SULFENYLATION; POTENT INHIBITORS; EFFICIENT CATALYST; ELECTRON-TRANSFER; Nitrogen heterocycles; ACCEPTORLESS DEHYDROGENATION; BIOLOGICAL EVALUATION; Oxidation; Synthetic methods; Indoles; METAL-FREE; N-HETEROCYCLES
• ISSN: 1434-193X; 1099-0690
• DOI: 10.1002/ejoc.202000508

We report an aerobic oxidative C–H sulfenylation of aryl‐fused cyclic amines with various thiols catalyzed by flavin/I2 for the first time. While flavin I catalyzed the C–H sulfenylation of indolines to afford 3‐sulfenylindoles, flavin II enabled transformations resulted in substitution at the position para to the N atom on the aryl ring to obtain 6‐sulfenylquinolines. The advantages of this metal‐free oxidative C–S coupling approach utilizing ambient oxygen as the terminal oxidant were that it was conducted under mild conditions with good atom‐efficiency and excellent functional compatibility. A metal‐free aerobic oxidative C–H sulfenylation of aryl‐fused cyclic amines with various thiols was developed with excellent functional compatibility. While flavin I catalyzed the C–H sulfenylation of indolines to afford 3‐sulfenylindoles, flavin II enabled transformations resulting in substitution at the position para to the N atom on the aryl ring to obtain 6‐sulfenylquinolines.