Photocatalyzed Radical Migration and C-H Oxidation Enabling Access to Terminal Trifluoromethylated Ketones
Yuhong Ma1, Man Chen1, Huanyi Guo1
1Guizhou Provincial Key Laboratory of Innovation and Manufacturing for Pharmaceuticals, Department of Pharmacy, Zunyi Medical University, Zunyi563000, China.
Abstract:
A visible-light-driven photocatalyzed C-H functionalization strategy for the synthesis of terminal trifluoromethylated ketones has been developed via 1,5- and 1,6-hydrogen atom transfer (1,5-HAT) under mild conditions with Ir(ppy)3 as the photocatalyst in good to excellent yields. Mechanistic studies involving radical trapping experiments, 18O-labeling, and UV-vis spectroscopy support a radical pathway. The method exhibits broad substrate scope and good functional group tolerance, providing a practical approach to access terminal trifluoromethylated ketones.
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