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![[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F59739.jpg&w=3840&q=50)
[(DPEPhos)(bcp)Cu]PF6: A General and Broadly Applicable Copper-Based Photoredox Catalyst
Published on: May 21, 2019
External Photosensitizer-Free, Purple Light-Mediated C-H Alkylation of Heterocycles with Unactivated Alkyl Iodides
Jian-Wei Li1,2, Jiang Bai1,2, Ruchun Yang1,2
1Jiangxi Provincial Key Laboratory of Organic Functional Molecule, Jiangxi Science and Technology Normal University, Nanchang 330013, China.
Abstract:
Herein, we describe an operationally simple and photosensitizer-free direct C-H alkylation of heterocycles protocol driven by purple light irradiation, which exhibits excellent scalability and broad functional group tolerance. Investigations into substrate scope confirm the versatility of this strategy, demonstrating high compatibility with various heterocycles, including benzothiazoles, benzimidazoles, azauracils, coumarins, isoquinolines, aza-uridine, and others. Mechanistic studies reveal that the photodriven alkylation proceeds via a sequential excited benzothiazole oxidation of Et3N, α-aminoalkyl radical-promoted halogen atom transfer, radical-radical coupling, and rearomatization.
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