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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Visible-light-induced cascade chromone cyclization/chalcogenation to access 3-chalcogenyl-chromones using elemental
Tao Guo1, Chuanhu Gao1, Zhonghui Li1
1School of Chemistry and Chemical Engineering, Henan University of Technology, Zhengzhou, Henan 450001, P. R. China.
Abstract:
A mild and efficient visible-light-induced cascade undergoing a chromone cyclization/chalcogenation at room temperature has been developed. This three-component reaction employs user-friendly elemental S8 and Se as the chalcogenide source, providing an attractive route for the convenient synthesis of 3-chalcogenyl-chromones with a wide substrate scope and good functional group tolerance.
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