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.
A novel synthetic approach to fluorine-containing acetylenic compounds based on Nicholas reaction
作者:Tsutomu Konno、Go Nagai、Takashi Ishihara
DOI:10.1016/j.jfluchem.2005.11.009
日期:2006.5
The fluorine-containing dicobalthexacarbonyl complex, prepared readily from γ-fluoroalkylated propargyl acetates and Co2(CO)8, reacted smoothly with various nucleophiles at the propargylic position, followed by oxidative decomplexation under the influence of Fe(NO3)3, to afford fluoroalkylated alkynes bearing various types of alkyl side chains in good to high yields.
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
The concise preparation of 4,4,4-trifluorobut-2-yn-1-ones by the oxidation of the readily accessible corresponding propargylic alcohols as well as their utilization as Michael acceptors for the construction of aromatic and heteroaromatic compounds are reported.