Gold(III)-Catalyzed Formal [3 + 2] Annulations of <i>N</i>-Acyl Sulfilimines with Ynamides for the Synthesis of 4-Aminooxazoles
作者:Xianhai Tian、Lina Song、Chunyu Han、Cheng Zhang、Yufeng Wu、Matthias Rudolph、Frank Rominger、A. Stephen K. Hashmi
DOI:10.1021/acs.orglett.9b01011
日期:2019.4.19
A gold-catalyzed formal 1,3-dipolar [3 + 2] annulation using readily accessible N-acyl sulfilimines and ynamides is reported. This reaction includes the cleavage of a N–S bond and subsequent C–O bond formation. In total, 30 oxazole derivatives bearing diverse functionalities could be prepared in 43–98% yield from the corresponding sulfilimines and ynamides.
vinyl dichlorides and electron deficient amides as the starting material is described. In the absence of transition-metal catalyst, the reaction proceeds under mild reaction conditions in open air and thus rendering a convenient operation. This strategy is not only suitable for both terminal and internal ynamide synthesis but also amenable for large-scale preparation. Broad substrate scopes with respect
The synthesis of ynamides in water was achieved by a micellarcatalysis strategy using rosin‐based surfactant APGS‐550‐M, which can be easily prepared from natural abundant biomass.
Borane-Catalyzed Selective Hydrosilylation of Internal Ynamides Leading to β-Silyl (<i>Z</i>)-Enamides
作者:Youngchan Kim、Ramesh B. Dateer、Sukbok Chang
DOI:10.1021/acs.orglett.6b03485
日期:2017.1.6
We have developed a borane-catalyzed regio- and stereoselectivehydrosilylation of internal ynamides for the first time. The scope of ynamide substrates and silane reactants was broad undermild reaction conditions, affording synthetically versatile β-silyl (Z)-enamide products. The observed stereoselectivity was reasoned to be due to the β-silicon effect on a postulated ketene iminium intermediate
Copper-Mediated Selective Cross-Coupling of 1,1-Dibromo-1-alkenes and Heteronucleophiles: Development of General Routes to Heterosubstituted Alkynes and Alkenes
site-selective, double, or alkynylative cross-coupling, therefore providing divergent and straightforward entries to numerous building blocks such as bromoenamides, ynamides, ketene N,N-acetals, bromoenol ethers, ynol ethers, keteneO,O-acetals, or vinylphosphonates and further expanding the copper catalysis toolbox with useful and versatile processes.