HFO‐1234yf as a CF
<sub>3</sub>
‐Building Block: Synthesis and Chemistry of CF
<sub>3</sub>
‐Ynones
作者:Ben J. Murray、Thomas G. F. Marsh、Dmitri S. Yufit、Mark A. Fox、Antal Harsanyi、Lee T. Boulton、Graham Sandford
DOI:10.1002/ejoc.202001071
日期:2020.10.22
diisopropylamide (LDA) leads to formation of lithium 3,3,3‐trifluoropropynide, addition of which to a range of aldehydes formed CF3‐alkynyl alcohol derivatives on multigram scale, which were oxidised using Dess‐Martin periodinane (DMP) to give substituted CF3‐ynones with minimal purification required. Michael‐type additions of alcohol and amine nucleophiles to CF3‐ynones are rapid and selective, affording
The preparation and cycloaddition reaction of 1-sulfonyl-1-trifluoromethyl allenes
作者:Jun-Li Li、Xian-Jin Yang、Min Jiang、Jin-Tao Liu
DOI:10.1016/j.tetlet.2017.07.050
日期:2017.8
A series of 1-sulfonyl-1-trifluoromethyl allenes were prepared for the first time from commercial available 2-bromo-3,3,3-trifluoropropene. Cycloadditionreaction of these trifluoromethylated allenes with nitrones occured readily under mild conditions, giving the corresponding trifluoromethylated isoxazolidines in high yields.
Isomeric fluorinated α‐bromoenones react with dinucleophilic β‐mercaptoalcohols in CH2Cl2 at room temperature in the presence of Et3N in a multistep process. Depending on the position of the CF3 group, different O,S‐heterocycles or non‐cyclic products were obtained. With 3‐bromo‐1,1,1‐trifluorobut‐3‐en‐2‐ones derivatives of 1,4‐oxathianes were formed, but isomeric2‐bromo‐4,4,4‐trifluorobut‐2‐en‐1‐ones
Highly Enantioselective [3 + 2] Annulation of 3-Butynoates with β-Trifluoromethyl Enones Promoted by an Amine−Phosphine Binary Catalytic System
作者:Huanzhen Ni、Yee Lin Wong、Mingyue Wu、Zhaobin Han、Kuiling Ding、Yixin Lu
DOI:10.1021/acs.orglett.0c00681
日期:2020.3.20
enantioselectivities. A unique catalytic system consisting of a simple amine and a chiralphosphine was devised, and the synergistic play of Lewis basic amine and phosphine was crucial for alkyne isomerization and subsequent cyclization. The protocol disclosed herein allows facile activation of 3-butynoates in phosphine-mediated asymmetric transformations.
An iron-catalyzed thiocyclization of propynols with aryl disulfides has been developed for the synthesis of trifluoromethylated benzothiophenes. The one-pot tandem reaction involves Meyer–Schuster rearrangement of propynols and radical cyclization through C–Hfunctionalization of aryl disulfides. A variety of 2-trifluoroacyl benzothiophenes were prepared in moderate to good yields with good functional-group