The Early Years of 2,2′-Bipyridine—A Ligand in Its Own Lifetime

The first fifty years of the chemistry of 2,2'-bipyridine are reviewed from its first discovery in 1888 to the outbreak of the second global conflict in 1939. The coordination chemistry and analytical applications are described and placed in the context of the increasingly sophisticated methods of characterization which became available to the chemist in this time period. Many of the "simple" complexes of 2,2'-bipyridine reported in the early literature have been subsequently shown to have more complex structures.