Vinyl nosylates as partner in copper and silver co-catalyzed Sonogashira cross-coupling reactions
作者:Nicolas P. Cheval、Barbara Hoffmann、Anna Dikova、Fatih Sirindil、Philippe Bertus、Aurélien Blanc、Jean-Marc Weibel、Patrick Pale
DOI:10.1016/j.tet.2018.10.017
日期:2018.12
Vinylnosylates, readily obtained from β-dicarbonyl derivatives, could be efficiently engaged in Sonogashira cross-couplingreactions, either cocatalyzed by copper or silver salts. The para-nitrobenzenesulfonate (nosylate) group allows this coupling to be performed under very mild conditions (room temperature). These new leaving group and mild conditions could be applied to the synthesis of acetylenic
Syntheses of 4-(1-alkynyl)-2(5H)-furanones and coumarins via the palladium catalyzed cross-coupling reactions of potassium alkynyltrifluoroborates
作者:George W. Kabalka、Gang Dong、Bollu Venkataiah
DOI:10.1016/j.tetlet.2004.04.150
日期:2004.6
An efficient synthesis of 4-(1-alkynyl)-2(5H)-furanones has been developed utilizing a palladiumcatalyzed coupling reaction of β-tetronic acid bromide with potassium alkynyltrifluoroborates in the absence of base. 4-Alkynylcoumarins were also synthesized using this method. The reactions are straightforward and the yields are excellent.
Racemic 4,5-disubstitued 5H-furan-2-ones have been selectively synthesized by addition of 1.2-1.6 equiv of aryl, alkenyl or 1-alkynyl halides and catalytic amounts of Pd(OAc)(2) and a soft ligand such as tri-2-furylphosphine or triphenylarsine to the reaction mixtures obtained by treatment of 3-ynoic acids with 1.1 equiv of t-BuOK in DMSO at 20 degrees C. (C) 1998 Elsevier Science Ltd. All rights reserved.