Synthesis of Amino-Functionalized 2,2′-Bipyridines

Amino-functionalized 2,2′-bipyridines are versatile building blocks for the synthesis of sophisticated chelating ligands with the 2,2′-bipyridine core. The 4-, 5-, and 6-substituted 2-chloro- and 2-bromopyridine building blocks were prepared and coupled to symmetrically and non-symmetrically diamino-functionalized compounds by homo- and cross-coupling procedures. Further transformations were carried out to demonstrate the synthetic versatility of these compounds and the employed procedures.