Transition Metal-Catalyzed Reactions
소속 :
연사 : Prof. Eun Jin Cho(Hanyang University, Department of Applied Chemistry)
일시 : 2012-03-22 17:00 ~
장소 : 500동 목암홀
일 시 : 2012년 3월 22일 오후 5시
장 소 : 500동 목암홀
-Abstract-
The development of methods for the introduction of trifluoromethyl groups onto aromatic rings or alkenyl groups has been of great interest due to the unique physical and biological activities of compounds containing trifluoromethyl groups. We investigated a palladium-catalyzed trifluoromethylation of aryl and heteroaryl chlorides using TESCF3 and KF as a trifluoromethyl source and its activator, respectively.
Both electron-deficient and rich substrates including ortho-substituted substrates provided the corresponding trifluoromethylated products in excellent yields. This process exhibits compatibility with a wide range of functional groups. In addition, vinyl triflates and vinyl nonaflates can also be applied in this process to give trifluoromethyl alkenyl compounds.
Another method has been developed for the visible light-induced trifluoromethylation of heterocyclic compounds. A variety of electron-rich heterocycles were transformed into trifluoromethylated products by using CF3I as the trifluoromethyl radical source and Ru(bpy)3Cl2 as the photocatalyst under mild reaction conditions. This operationally simple and eco-friendly process can introduce trifluoromethyl groups without prefunctionalization.
Upon activation with an electrophilic transition metal catalyst such as platinum and gold, a propargylic acetate undergoes competing [1,2]- and [1,3]-acyloxy migration. The reaction pathway type depends on the reaction temperature as well as the substituent pattern around the alkyne. The nature of the catalyst also affects the reaction course. The reactions provided clear evidence for the interconversion between carbenoid and allene intermediates.
장 소 : 500동 목암홀
-Abstract-
The development of methods for the introduction of trifluoromethyl groups onto aromatic rings or alkenyl groups has been of great interest due to the unique physical and biological activities of compounds containing trifluoromethyl groups. We investigated a palladium-catalyzed trifluoromethylation of aryl and heteroaryl chlorides using TESCF3 and KF as a trifluoromethyl source and its activator, respectively.
Both electron-deficient and rich substrates including ortho-substituted substrates provided the corresponding trifluoromethylated products in excellent yields. This process exhibits compatibility with a wide range of functional groups. In addition, vinyl triflates and vinyl nonaflates can also be applied in this process to give trifluoromethyl alkenyl compounds.
Another method has been developed for the visible light-induced trifluoromethylation of heterocyclic compounds. A variety of electron-rich heterocycles were transformed into trifluoromethylated products by using CF3I as the trifluoromethyl radical source and Ru(bpy)3Cl2 as the photocatalyst under mild reaction conditions. This operationally simple and eco-friendly process can introduce trifluoromethyl groups without prefunctionalization.
Upon activation with an electrophilic transition metal catalyst such as platinum and gold, a propargylic acetate undergoes competing [1,2]- and [1,3]-acyloxy migration. The reaction pathway type depends on the reaction temperature as well as the substituent pattern around the alkyne. The nature of the catalyst also affects the reaction course. The reactions provided clear evidence for the interconversion between carbenoid and allene intermediates.
