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Updated: Dec 24, 2025
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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Pd-Catalyzed Oxidative Annulation of Aryl Ethers with Alkynes: Synthesis of Functionalized Spirocycles and
Shiyong Peng1,2, Zhonghao Sun1, Huijuan Zhu1
1Institute of Medicinal Plant Development, Chinese Academy of Medical Science and Peking Union Medical College, Beijing 100193, P. R. China.
Abstract:
Palladium-catalyzed dearomative [2+2+1] annulations of aryl ethers with alkynes are reported via para-selective C-H functionalization, providing highly functionalized spirocyclohexadienones in moderate to excellent yields under mild reaction conditions. Importantly, mechanistic investigation indicated an unusual C-O bond cleavage was involved. Moreover, polyarylated naphthalenes could be obtained via oxidative [2+2+2] annulation by tuning aryl ethers from monomethoxybenzenes to polymethoxybenzenes under an identical catalytic system.
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