Synthesis and characterization of 2,6-bis-hydrazinopyridine, and its conversion to 2,6-bis-pyrazolylpyridines

2,6-Bis-hydrazinopyridine has been prepared and characterized for the first time. This material is useful for the preparation of a wide variety of 2,6-bis-pyrazolylpyridines. This approach represents the most efficient preparation to date of sterically crowded 2,6-bis-pyrazolylpyridines, and the only method for the preparation of pyrazolylpyridines containing unsymmetrically 3′,5′-disubstituted pyrazoles with the larger groups in the 5′ positions. © 2006 Elsevier Ltd. All rights reserved