Abstract A one-step, regioselective synthesis of annelated symmetric and asymmetric 3, 3′- disubstituted 2, 2′-bipyridines by cobalt (I)-catalyzed [2+ 2+ 2] cycloadditions between 5- hexynenitrile and 1, 3-diynes is described. In the symmetric case, the total regioselectivity of the first cycloaddition is ensured electronically by the conjugation of the triple bonds, and for aminomethylated diynes that of the second is ensured by the cobalt coordinating to the ...
