Enamides and Enesulfonamides as Nucleophiles: Formation of Complex Ring Systems through a Platinum(II)-Catalyzed Addition/Friedel−Crafts Pathway
作者:Jennifer A. Kozak、Jennifer M. Dodd、Tyler J. Harrison、Katherine J. Jardine、Brian O. Patrick、Gregory R. Dake
DOI:10.1021/jo901512m
日期:2009.9.18
(enesulfonamides and enamides) tethered to an 1-arylalkynyl fragment undergo a platinum(II)-catalyzed tandem alkyne addition/Friedel−Crafts ring closure to form nitrogen-containing polycyclic structures. Regioselectivity in the initial addition of the enesulfonamide or enamide nucleophile to the platinum(II)−alkyne complex is important. Electron-rich arenes and heterocycles led to the formation of products
Platinum(II)-Catalyzed Cyclizations Forming Quaternary Carbon Centers, Using Enesulfonamides, Enecarbamates, or Enamides as Nucleophiles
作者:Tyler J. Harrison、Brian O. Patrick、Gregory R. Dake
DOI:10.1021/ol062939g
日期:2007.1.1
Cyclic enesulfonamides, enecarbamates, or enamides tethered to an alkyne cyclize readily with use of platinum(II) chloride. This reaction generates quaternary-substituted carbon centers within simple spiro-fused or more complex tri- and tetracyclic heterocyclic ring systems. The yields for this process range from 50% to 83%. [reaction: see text].