Site-selectivity in hydrazinolysis of 3,4'-bis-(functionalized carbonyl)-4,3'-bis(pyrazolyl)ketones. A convenient synthesis of 4-(pyrazol-3-yl)-2H-pyrazolo[3,4-d]-pyridazines
摘要:
Reaction of hydrazine hydrate with 3,4-bis-(functionalized carbonyl)-4,3-bis(pyrazolyl)ketones proceeds regioselectively affording the corresponding 4-(pyrazol-3-yl)-2H-pyrazolo[3,4-d]pyridazine derivatives in high yields. The structures of the products were determined by spectroscopic and elemental analyses and supported by comparison with the possible isomers prepared by an independent route.