Synthesis of 2-hetarylimidazo[4,5-d]pyridazine derivatives
摘要:
2-Chloropyridine-3,4-diamine reacted with hetarenecarboxylic acids (pyridine-2-, pyridine-3-, and pyridine-4-carboxylic acids and 6-oxo-1,6-dihydropyridazine-3-carboxylic acid) in polyphosphoric acid at 160-170 degrees C to give the corresponding 2-hetarylimidazo[4,5-c]pyridin-4-ones. Nitration of the latter with a mixture of concentrated nitric and sulfuric acids led to the formation of 2-hetaryl-7-nitroimidazo[4,5-c]pyridin-4-ones which were converted into 2-hetaryl-7-methylimidazo[4,5-d]pyridazin-4-ones by the action of hydrazine hydrate at 140-150 degrees C.
Synthesis of 2-hetarylimidazo[4,5-d]pyridazine derivatives
摘要:
2-Chloropyridine-3,4-diamine reacted with hetarenecarboxylic acids (pyridine-2-, pyridine-3-, and pyridine-4-carboxylic acids and 6-oxo-1,6-dihydropyridazine-3-carboxylic acid) in polyphosphoric acid at 160-170 degrees C to give the corresponding 2-hetarylimidazo[4,5-c]pyridin-4-ones. Nitration of the latter with a mixture of concentrated nitric and sulfuric acids led to the formation of 2-hetaryl-7-nitroimidazo[4,5-c]pyridin-4-ones which were converted into 2-hetaryl-7-methylimidazo[4,5-d]pyridazin-4-ones by the action of hydrazine hydrate at 140-150 degrees C.