Synthesis of 2,2′-bipyridines:: Versatile building blocks for sexy architectures and functional nanomaterials

The latest synthetic strategies to prepare 2,2'-bipyridine and its mono-substituted, symmetrical and unsymmetrical 3,3'-, 4,4'-, 5,5'-, and 6,6'-disubstituted derivatives are critically discussed and evaluated. Different coupling procedures to achieve new symmetrical and unsymmetrical functionalized 2,2'-bipyridines, such as Stille-type, Negishi-type, and Su-zuki-type cross-coupling reactions are discussed in detail. Moreover, condensation procedures that allow further variations are presented. The application of functional group transformations for access to additional groups is examined. ((C) Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2004).