Visible-Light-Induced C-H Alkylation of 1,2,4-Triazine-3,5(2H,4H)-diones via Infrequent 1,2-Hydrogen-Atom Transfer
Mi Wang1, Yangyang Wang2,3, Jie Wang2
1Key Laboratory of Drug-Targeting and Drug Delivery System of the Education Ministry and Department of Medicinal Chemistry, West China School of Pharmacy, Sichuan University, No. 17 Southern Renmin Road, Chengdu, Sichuan 610041, China.
Abstract:
1,2,4-Triazine-3,5(2H,4H)-diones are widely present in various drug molecules and bioactive molecules. A visible-light-driven C-H alkylation of 1,2,4-triazine-3,5(2H,4H)-diones via 1,2-hydrogen-atom transfer (1,2-HAT) of amide radicals is first reported, providing an environmentally friendly and sustainable pathway to enrich the structural and functional diversity of 1,2,4-triazine-3,5(2H,4H)-diones. This novel protocol is characterized by mild and metal-free reaction conditions, an operationally simple method, and good functional group tolerance. To our delight, other heterocycles, such as isoquinoline and coumarin, also undergo alkylation reactions to construct C(sp2)-C(sp3) bonds via infrequent 1,2-HAT under current conditions.
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