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α-Alkylation of Ketones with Alkenes Enabled by Photoinduced Activation of Silyl Enol Ethers in the Presence of a Small Amount of Water

Tsubasa Hirata, Yoshihiro Ogasawara, Yasuhiro Yamashita* and Shu̅ Kobayashi*

*Department of Chemistry, School of Science, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan, Email:,

T. Hirata, Y. Ogasawara, Y. Yamashita, S. Kobayashi, Org. Lett., 2021, 23, 5693-5697.

DOI: 10.1021/acs.orglett.1c01824 (free Supporting Information)

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Under blue-light irradiation with 1,2,3,5-tetrakis(carbazol-9-yl)-4,6-dicyanobenzene as photocatalyst, silyl enol ethers reacted with alkenes in the presence of a small amount of water to afford α-alkylated products in very good yields. A thiol cocatalyst was found to expand the substrate scope of the reaction.

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proposed mechanism


Key Words

cyclohexanones, organocatalysis, photochemistry

ID: J54-Y2021