Nickel-Catalyzed Cycloaddition of Alkynes and Isocyanates
作者:Hung A. Duong、Michael J. Cross、Janis Louie
DOI:10.1021/ja046477i
日期:2004.9.1
A mild and general route for preparing 2-pyridones from isocyanates and diynes is described. Ni imidazolyidene complexes were used to mediate cyclizations between both internal and terminal diynes with aryl and alkyl isocyanates. In addition, the efficacy of this protocol allows for the preparation of a fused seven-membered pyridone and for three component cyclizations.
Ruthenium(II)-Catalyzed Cycloaddition of 1,6-Diynes with Isocyanates Leading to Bicyclic Pyridones
[GRAPHICS]A ruthenium(II) complex possessing a planar Cp* ligand, Cp*Ru(cod)Cl, effectively catalyzed the [2 + 2 + 2] cycloaddition of I,g-diynes with isocyanates to afford bicyclic pyridones in 58-87% yields.