Visible light photocatalytic cross-coupling and addition reactions of arylalkynes with perfluoroalkyl iodides
作者:Yelan Xiao、Yuen-Kiu Chun、Shun-Cheung Cheng、Ruoyang Liu、Man-Kit Tse、Chi-Chiu Ko
DOI:10.1039/d0ob01767a
日期:——
of arylalkynes with perfluoroalkyl iodides have been developed. Through slight modifications of the reaction conditions, reactions that are selective for the preparation of the C–C coupling product (perfluoroalkyl alkynes) and the addition products (iodo-perfluoroalkyl substituted alkenes) can be achieved. These reactions work well with different types of alkynes and perfluoroalkyl iodides. As the iodide
1-Aryl- or 1-alkenyl-2-(perfluoroalkyl)acetylenes were produced in high yields by the coupling reaction of aryl or alkenyl iodides with (perfluoroalkynyl)zinc compounds prepared from the corresponding (perfluoroalkyl)acetylenes in the presence of Pd catalyst.
Treatment of per- or polyfluoroalkylated vinyl iodides 5 with 2 equiv. of n-BuLi in THF produced the corresponding lithium acetylides in situ, which were transformed into zinc acetylides by the addition of ZnCl2.TMEDA complex into the reaction mixture. The in situ generated zinc acetylides were exposed to the cross-coupling conditions such as ArI/cat. Pd(PPh3)(4), reflux, 6-12 h, giving rise to the desired per- or polyfluoroalkylated acetylenes in high yields. In the case of trifluoromethylated acetylene, commercially available 2-bromo-3,3,3-trifluoropropene 6 could also be used instead of 5 as the starting material. In the acetylenes having a fluoroalkyl group and an aliphatic side chain, vinyl iodides 7, prepared by radical addition of perfluoroalkyl iodide to terminal acetylenes, were treated with t-BuOK at room temperature or at the reflux temperature of benzene, affording the desired compounds in good yields. (C) 2003 Elsevier Ltd. All rights reserved.
Perfluoroalkylation of Terminal Alkynes with Perfluoroalkyl Iodides Catalyzed by an Iron Salt
作者:Wei Li、Changfa Liang、Baogui Luo、Zhenhui Wang、Hengyuan Li、Xiaofeng Li、Huanjian Yang、Huaifeng Li