Catalyst-Free Photoinduced ortho C-H Heteroarylation of Phenols
Da-Liang Zhu1,2, Chuanpeng Wang1, Jie Li1
1School of Chemistry and Environmental Engineering, Analysis and Testing Centre, Yancheng Teachers University, Yancheng 224007, China.
Abstract:
Visible-light-induced ortho C-H heteroarylation of free phenols with heteroaryl halides in the absence of both transition-metal and photoredox catalysts has been developed. This reaction proceeds through single-electron transfer of the excited charge-transfer complex between the pyridine substrate and tBuONa, followed by addition to the phenol. This heteroarylation was tolerant toward diverse functional groups and has been demonstrated with a gram-scale reaction.
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