A cationic palladium(II)/(S)-xyl-Segphos complex catalyzes enantioselective cycloisomerizations of N-alkenyl arylethynylamides leading to axiallychiral 4-aryl-2-pyridones in high yields with high ee values. The present catalysis represents the first enantioselective construction of axialchirality by the transition-metal-catalyzed cycloisomerization.
On the Synthesis of Arylpropiolic Acids and Investigations towards the Formation of Vinyl Chlorides by HCl Addition During Esterification Reactions
作者:Marko Hapke、Karolin Kral、Anke Spannenberg
DOI:10.1055/s-0030-1258399
日期:2011.2
The synthesis protocol for the preparation of different arylpropiolic acids using the Negishi reaction and the addition of HCl to the alkyne moiety of these acids in subsequent esterificationreactions using SOCl2 was examined. alkynes - esterification - additionreactions - vinyl chlorides - Negishi reaction