転位反応の研究 (第7報)
ピリダゾン誘導体からピラゾロン誘導体への縮環反応 その2
1963 年 83 巻 9 号 p. 819-824
詳細
1963 年 83 巻 9 号 p. 819-824
Various substituent groups were introduced into 3, 5- or 3, 4-positions of 1-phenyl-6(1H)-pyridazinone ring and their condensation to 1-phenylpyrazolonecarboxylic acid by treatment with alkali hydroxide or hydrobromic acid was examined. It was found that 3, 4-substituted derivatives do not undergo condensation but 3, 5-substituted derivatives were found to undergo rearrangement to 1-phenyl-3-hydroxy-5-pyrazolecarboxylic acid if the starting compounds and reaction conditions were so chosen to form the expected intermediates 1-phenyl-3, 5-dihydroxy-6(1H)-pyridazinone (B) and 1-phenyl-2-methyl-5-hydroxy-3, 6(1H, 2H)-pyridazinedione (C).
