A novel, efficient, and mild synthetic route for the preparation of 2-aminopyridines via ruthenium-mediated [2 + 2 + 2] cycloaddition of α,ω-diynes and cyanamides has been developed. This atom-economical catalytic process demonstrated remarkable regioselectivities to access pyridine derivatives of high synthetic utility.
Nickel-Catalyzed [2+2+2] Cycloaddition of Diynes and Cyanamides
作者:Ryan M. Stolley、Michael T. Maczka、Janis Louie
DOI:10.1002/ejoc.201100428
日期:2011.7
A variety of bicyclic N,N-disubstituted 2-aminopyridines have been prepared from diynes and cyanamides by nickel-catalyzed [2+2+2] cycloaddition reactions. The reactions proceeded at room temperature with low catalyst loading to afford 2-aminopyridines in good to excellent yields. The method is amenable to both internal and terminal diynes and proceeds in a regioselective manner. A number of cyanamides
Iron-Catalyzed Formation of 2-Aminopyridines from Diynes and Cyanamides
作者:Timothy K. Lane、Brendan R. D’Souza、Janis Louie
DOI:10.1021/jo3012418
日期:2012.9.7
Diynes and cyanamides undergo an iron-catalyzed [2 + 2 + 2] cycloaddition to form highly substituted 2-aminopyridines in an atom-efficient manner that is both high yielding and regioselective. This system was also used to cyclize two terminal alkynes and a cyanamide to afford a 2,4,6-trisubstituted pyridine product regioselectively.