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Facile Preparation of 2Z,4E-Dienamides by the Olefination of Electron-deficient Alkenes with Allyl Acetate
Published on: June 21, 2017
Manganese(I)-Catalyzed Direct C-H Allylation of Arenes with Allenes
Shi-Yong Chen1, Qingjiang Li1,2, Honggen Wang1
1School of Pharmaceutical Sciences, Sun Yat-sen University , Guangzhou, 510006, China.
Abstract:
Polysubstituted allyl groups, for example, the prenyl group, are valuable synthetic handles and widely encountered in bioactive compounds. Reported herein is a manganese(I)-catalyzed direct C-H coupling with allenes for the efficient assembly of allylated arenes. The protocol offers an extremely high level of atom-economy and is particularly suited for the introduction of 1,1-disubstitiuted allyl groups, as exemplified by the quantitative syntheses of a variety of prenylated indoles. The practicality of this method was evidenced by a gram-scale synthesis with a lower catalyst loading of manganese(I) (2.5 mol %, 95% yield). Experimental mechanistic studies were conducted, and a possible reaction mechanism was proposed.
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