Remarkable rate acceleration of SmI3-mediated iodination of acetates of Baylis-Hillman adducts in ionic liquid: facile synthesis of (Z)-allyl iodides  

作　　者：LIU Yun-kui ZHENG Hui XU Dan-qian XU Zhen-yuan ZHANG Yong-min 

机构地区：[1]State Key Laboratory Breeding Base of Green Chemistry-Synthesis Technology, Zhejiang University of Technology, Hangzhou 310014, China

出　　处：《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》2006年第3期193-197,共5页浙江大学学报（英文版）B辑（生物医学与生物技术）

基　　金：Project (No. 2004C21032) supported by the Key Technology R & DProgram of Zhejiang Province, China

摘　　要：Stereoselective transformation of Baylis-Hillman acetates I into corresponding （Z）-allyl iodides 2 has been achieved by treatment of I with samarium triiodide in THF. Remarkable rate acceleration of samarium triiodide-mediated iodination of 1 was found when ionic liquid 1-n-butyl-3-methyl-imidazolium tetrafluroborate （[bmim]BF4） was used as reaction media in stead of THF. This novel approach proceeds readily at 50 ℃ within a few minutes to afford （Z）-allyl iodides 2 in excellent yields. A mechanism involving stereoselective iodination of the acetates of Baylis-Hillman adducts by samarium triiodide is described, in which a six-membered ring transition state played a key role in the stereoselective formation of 2.Stereoselective transformation of Baylis-Hillman acetates 1 into corresponding (Z)-allyl iodides 2 has been achieved by treatment of 1 with samarium triiodide in THF. Remarkable rate acceleration of samarium triiodide-mediated iodination of 1 was found when ionic liquid 1-n-butyl-3-methyl-imidazolium tetrafluroborate ([bmim]BF4) was used as reaction media in stead of THF. This novel approach proceeds readily at 50 °C within a few minutes to afford (Z)-allyl iodides 2 in excellent yields. A mechanism involving stereoselective iodination of the acetates of Baylis-Hillman adducts by samarium triiodide is described, in which a six-membered ring transition state played a key role in the stereoselective formation of 2.

关 键 词：Baylis-Hillman adduct （Z）-allyl iodide Samarium triiodide Ionic liquid 

分 类 号：Q4[生物学—生理学]