The reaction of methyl o-(2-R-ethynyl)benzoates with hydrazine affords either fused 4-R-methylphthalazin-1-ones or 2-amino-3-R-methylideneisoindolin-1-ones. The latter are on treatment with KOH undergo recyclization into the corresponding 4-R-methylphthalazin-1-ones.
邻-(2-R-
乙炔基)
苯甲酸甲酯与
肼反应得到稠合的 4-R-甲基
酞嗪-1-酮或 2-
氨基-3-R-亚甲基
异吲哚啉-1-酮。后者用 KOH 处理,再循环成相应的 4-R-methylphthalazin-1-ones。