Divergent C-C and C-N Cross-Coupling of Aryl Halides with Formamide via Photoredox/Nickel Dual Catalysis
Jun Xu1,2, Xiang-Li Guo2, Yan Chen2
1School of Energy Materials and Chemical Engineering, Hefei University, Hefei 230601, P. R. China.
Abstract:
A photocatalyst-tuned, Ni-catalyzed system enables switchable C-C or C-N coupling of aryl halides with formamide, directly synthesizing unprotected benzamides or N-arylformamides. Selectivity is governed by PC/base pairs. Benzophenone/K2HPO4 affords C-C-coupled benzamides, while thioxanthone TXO/NaHCO3 yields C-N-coupled N-arylformamides. This atom-economical method exhibits a broad scope and excellent regioselectivity, providing a sustainable platform for synthesizing unprotected benzamides and N-arylformamides as valuable building blocks in organic synthesis.
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