Metal and Photocatalyst-Free Amide Synthesis via Decarbonylative Condensation of Alkynes and Photoexcited Nitroarenes
Rongqi Cui1, Qian Liao1, Yuanxia Zhao1
1State Key Laboratory of Fine Chemicals, School of Chemistry, Dalian University of Technology, Dalian 116024, China.
Abstract:
Depending on the intrinsic photoactivity of nitroarenes, we herein developed a practical Brønsted acid-catalyzed decarbonylative amide synthesis from alkynes and photoexcited nitroarenes without any metal or photocatalyst. This method exhibited compatibility with water and air, broad substrate applicability, marvelous functional group tolerance, and wide applications in scale-up synthesis, late-stage functionalization, and total synthesis. Mechanism studies and DFT calculations supported that a 1,3,2-dioxazole intermediate was involved, and gaseous carbon monoxide was the only byproduct during amide construction.
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