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Published on: June 10, 2021
Regioselective [2 + 1] photocycloaddition of 2-pyridones with diazo compounds
Fengya He1, Ziyi Sun1, Chenyue Li1
1Key Laboratory of Xin'an Medicine, Ministry of Education, Anhui University of Chinese Medicine, Hefei, Anhui, 230038, P. R. China. cgwu@ahtcm.edu.cn.
Abstract:
Herein, we report a novel regioselective [2 + 1] cyclization reaction of 2-pyridones with carbenes generated in situ via visible light irradiation, without the requirement for catalysts or additives. The diverse functional groups of 2-pyridones and diazo compounds exhibit good tolerance, enabling the rapid synthesis of highly valuable cyclopropanated dihydro-2-pyridone scaffolds with exceptional regio- and stereoselectivity. Furthermore, DFT calculations provide a comprehensive explanation for the regio- and stereoselectivity observed in the reaction.
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