Preparation of 3-methylquinoline-8-carboxylic acid
    1.
    发明授权
    Preparation of 3-methylquinoline-8-carboxylic acid 失效
    3-甲基喹啉-8-羧酸的制备

    公开(公告)号:US5130434A

    公开(公告)日:1992-07-14

    申请号:US571232

    申请日:1990-08-23

    IPC分类号: C07D215/48

    CPC分类号: C07D215/48

    摘要: 3-Methylquinoline-8-carboxylic acid I ##STR1## and derivatives thereof are prepared by reacting o-toluidine II or a derivative thereof ##STR2## with methacrolein II ##STR3## in 70-90% strength by weight sulfuric acid in the presence of iodine or of an iodine compound, and oxidizing the resulting 3,8-dimethylquinoline IV or a derivative thereof ##STR4## with nitric acid in a solution containing sulfuric acid, in the presence of vanadium ions, by a process in which, in the sulfuric acid-containing reaction solution of the 3,8-dimethylquinoline IV, the byproducts of the reaction are first decomposed by oxidation, the resulting 3,8-dimethylquinoline solution is concentrated by distillation and the 3,8-dimethylquinoline is then oxidized in situ with nitric acid to give the 3-methylquinoline-carboxylic acid.

    摘要翻译: 3-甲基喹啉-8-羧酸I I及其衍生物通过邻甲苯胺II或其衍生物II与甲基丙烯醛II III在70-90%重量比的硫酸中反应制备 碘或碘化合物的存在,并且在钒离子存在下,通过硝酸在含硫酸溶液中氧化得到的3,8-二甲基喹啉IV或其衍生物IV,其中 在3,8-二甲基喹啉IV的含硫酸的反应溶液中,首先通过氧化分解反应的副产物,然后通过蒸馏浓缩所得的3,8-二甲基喹啉溶液,然后将3,8-二甲基喹啉 用硝酸原位氧化得到3-甲基喹啉羧酸。