Remote γ-C(sp3)-H Activation of Masked Aliphatic Alcohols Enables Pyridone Ether Synthesis
Yong-Shui Hu1, Yang-Yang Tu1, Qian-Lin He1
1School of Chemistry and Chemical Engineering, Nanjing University of Science and Technology, Nanjing, Jiangsu 210094, China.
None:
A Pd(II)-catalyzed oxime ether-directed γ-C(sp3)-H activation of masked aliphatic alcohols has been developed, enabling selective C-O bond formation with electron-deficient pyridones. The use of N-fluorobenzenesulfonimide (NFSI) as a key oxidant is crucial for over-riding the conventional β-selectivity, thereby affording γ-functionalized products. This transformation exhibits a broad substrate scope and a high functional group tolerance. Overall, this strategy provides an efficient and practical approach to pyridone ether synthesis via remote C-H activation.
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