Activation of Trifluoromethylthio Moiety by Appending Iodonium Ylide under Copper Catalysis for Electrophilic Trifluoromethylation Reaction  

作　　者：Ibrayim Saidalimu Shugo Suzuki Etsuko Tokunaga Norio Shibata 

机构地区：[1]Department of Frontier Materials Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan [2]Department of Nanopharmaceutical Sciences,Nagoya Institute oF Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan

出　　处：《Chinese Journal of Chemistry》2016年第5期485-489,共5页中国化学（英文版）

摘　　要：A novel iodonium-ylide compound 2 that appends a trifluoromethylthio （SCF3） group is disclosed as a new, shelf-stable electrophilic trifluoromethylation reagent. Unlike known shelf-stable electrophilic trifluoromethylation reagents, 2 has a stable SCF3 group which is activated by appending iodonium ylide under copper catalysis via sul- fonium ylide to generate a cationic trifluoromethyl （CF3） species. Reagent 2 was found to be an efficient electro- philic trifluoromethylation reagent for a wide range of silyl enol ethers 3 under copper catalysis. Cyclic and acyclic a-trifiuoromethyl ketones 4 were obtained by reagent 2 in moderate to good yields. On the other hand, a difluoro- methylthio analogue 5 did not affect intermolecular transfer difluoromethylation to substrates. Instead, intramolecu- lar 1,4-migration proceeded similar to the Stevens rearrangement to provide 6 in 21% yield, independent of the presence of nucleophiles 3.A novel iodonium-ylide compound 2 that appends a trifluoromethylthio （SCF3） group is disclosed as a new, shelf-stable electrophilic trifluoromethylation reagent. Unlike known shelf-stable electrophilic trifluoromethylation reagents, 2 has a stable SCF3 group which is activated by appending iodonium ylide under copper catalysis via sul- fonium ylide to generate a cationic trifluoromethyl （CF3） species. Reagent 2 was found to be an efficient electro- philic trifluoromethylation reagent for a wide range of silyl enol ethers 3 under copper catalysis. Cyclic and acyclic a-trifiuoromethyl ketones 4 were obtained by reagent 2 in moderate to good yields. On the other hand, a difluoro- methylthio analogue 5 did not affect intermolecular transfer difluoromethylation to substrates. Instead, intramolecu- lar 1,4-migration proceeded similar to the Stevens rearrangement to provide 6 in 21% yield, independent of the presence of nucleophiles 3.

关 键 词：TRIFLUOROMETHYLATION DIFLUOROMETHYLATION iodine sulfur YLIDE 

分 类 号：O[理学]