Copper(I)-Catalyzed Asymmetric 1,3-Dipolar Cycloaddition of Azomethine Ylides with Fluorinated Imines: The Expanded Scope and Mechanism Insights
作者:Liang Wei、Qing-Hua Li、Chun-Jiang Wang
DOI:10.1021/acs.joc.8b01743
日期:2018.10.5
The mechanism of the Cu(I)/(S,Rp)-PPFOMe-catalyzed 1,3-dipolar cycloaddition of azomethine ylides with fluorinated aldimines has been studied using labeling experiments, control experiments, and linear effect experiments, which clearly ruled out the 1,3-DC/epimerization pathways and explained the unusal exo′-selective stereochemistry. This protocol allows for the preparation of a series of highly functionalized
使用标记实验,对照实验和线性效应实验研究了Cu(I)/(S,R p)-PPFOMe催化的1,3-偶极环偶氮亚甲基与氟化亚胺的加成反应的机理,明确排除了1,3- DC /差向异构化途径和解释了此项特殊的外切' -选择性的立体化学。该方案允许以良好的产率和优异的立体选择性制备一系列高度官能化的氟化咪唑烷。而且,目前的方法已经成功地扩展到通过内含物合成具有挑战性的,带有CF 3的季立构中心的咪唑烷类化合物。在相同的反应条件下,用三氟化酮亚胺对甲亚胺烷基化物进行1,3-DC选择性合成。
1-(Organoselanyl)perfluoroalkanols: A Stable and Efficient Precursor for Organoselenols
The 1-(organoselanyl)perfluoroalkanols 1, 3, 4, and 10 were successfully prepared and reactions with hexanoyl chlorides to produce the corresponding esters 5, 7, and 8, accompanied by the selenoesters 6 were conducted. The DBU-mediated alkylations of the heptafluorobutanols 4, 10, and the α-p-nitrobenzoate 2 with alkyl halides easily provided alkyl phenyl selenides 9a–9i and 11a–11c in good to high yields.