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
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
Decarbonylative Coupling of α-Keto Acids and Ynamides for Synthesis of β-Keto Imides
作者:Renjie Chen、Linwei Zeng、Bo Huang、Yangyong Shen、Sunliang Cui
DOI:10.1021/acs.orglett.8b01302
日期:2018.6.1
A novel decarbonylative coupling of α-keto acids and ynamides with extrusion of CO for synthesis of β-keto imides is reported. This process features mild reaction conditions, a broad substrate scope, and high efficiency. An isotope-labeling reaction and GC analysis were conducted to elucidate a plausible reaction mechanism.
Gold‐Catalyzed Intermolecular [4+2] Annulation of 2‐Ethynylanilines with Ynamides: An Access to Substituted 2‐Aminoquinolines
作者:Ximei Zhao、Xinlong Song、Hongming Jin、Zhongyi Zeng、Qian Wang、Matthias Rudolph、Frank Rominger、A. Stephen K. Hashmi
DOI:10.1002/adsc.201800341
日期:2018.7.16
A gold‐catalyzedintermolecular [4+2] annulation of easily accessible 2‐ethynylanilines with ynamides offers a highly region‐selective, modular, efficient, and atom‐economical strategy for the synthesis of substituted2‐aminoquinolines in up to 93% yield.