Synthesis of the Novel 4,4？- and 6,6？- Dihydroxamic - 2,2？-Bipyridines and Improved Routes to 4,4？- and 6,6？- Substituted 2,2？-Bipyridines and Mono-N-Oxide-2,2？-Bipyridine

the preparation of key precursors for many 2,2？-bipyridine derivatives such as 4,4？-dicarboxy- 2,2？-bipyridine (i), 6,6？-dicarboxy-2,2？-bipyridine- acid (ii), 4,4？-dinitro-2,2？-bipyridine-n,n-dioxide (iii), 6,6？-dicarbothioamide-2,2？-bipyridine (iv) and mono-n-oxide-2,2？-bipyridine (vii) through more efficient methods is described. the syntheses of the novel ligands 4,4？-dihydroxamic-2,2？-bipyridine (v) and 6,6？-dihydroxamic-2,2？-bipyridine (vi) are also reported.