The present invention is a process for producing 3-methyl-2-oxoindoline as defined by the following chemical formula (2), including heating of propionylphenylhydrazide as defined by the following chemical formula (1) in the presence of at least one kind of basic calcium compound, characterized in that an organic solvent withstanding at least at a temperature of 180°C in the presence of the basic calcium compound is employed by at least an amount of equal weight to that of the propionylphenylhydrazide. With the construction mentioned above, even when the amount of calcium oxide is reduced down to as little as 15 % of a conventionally used amount, at least 75 % of a corresponding yield attained conventionally has been achieved. That is, not only control of the reaction and easy after treatment but also a high yield has been achieved.
本发明是一种生产下
化学式(2)所定义的 3-甲基-2-氧代
吲哚啉的工艺,包括在至少一种碱性
钙化合物存在下加热下
化学式(1)所定义的丙酰基苯
肼,其特征在于在碱性
钙化合物存在下,使用至少与丙酰基苯
肼等重量的有机溶剂,其耐受温度至少为 180℃。根据上述结构,即使将
氧化钙的用量减少到常规用量的 15%,也能达到常规产量的至少 75%。也就是说,不仅能控制反应和易于处理,而且还能获得高产率。