Pd-Catalyzed Remote Site-Selective and Stereoselective C(Alkenyl)–H Alkenylation of Unactivated Cycloalkenes

• DOI: 10.1021/acs.joc.9b02797
• Publication Date: 2019-12-12T12:32:55Z
• Authors: Chun-Li Mao; Sheng Zhao; Zhong-Lin Zang; Lin Xiao; Cheng-He Zhou; Yun He; Gui-Xin Cai
• Keywords: 01 natural sciences; 0104 chemical sciences

A palladium-catalyzed alkenylation involving remote δ-position C(alkenyl)-H activation of cycloalkenes reacting with electron-deficient alkenes is described. This method features excellent site selectivity and stereoselectivity to efficiently afford only E-selective highly substituted 1,3-diene derivatives extra-ligand-free good functional group tolerance including estrone free N-H tryptamine under weakly alkaline conditions. Mechanistic studies suggest that picolinamide as a bidentate directing enables the formation unique alkenyl palladacycle intermediates.