An efficient process for the large-scale synthesis of 4-methylnicotinic acid is developed. The synthetic route utilized 2,6-dichloro-4-methylnicotinonitrile as the starting material, which was commercially available. The key step in the sequence was the reductive dechlorination in the presence of zinc and ammonia to provide an intermediate which was hydrolyzed to the described acid. The reaction parameters optimization and improvement of purification are also presented. This approach, suitable for batch processing, is of interest basically to research laboratories and also to suppliers in the research and fine chemicals market.

中文翻译：

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实用有效的大规模制备4-甲基烟酸

开发了一种大规模合成4-甲基烟酸的有效方法。合成路线以2,6-二氯-4-甲基烟腈为起始原料，可商购获得。序列中的关键步骤是在锌和氨的存在下进行还原性脱氯，以提供一种中间体，该中间体被水解为上述酸。还提出了反应参数的优化和纯化的改进。这种适用于批处理的方法基本上是研究实验室以及研究和精细化学品市场的供应商所感兴趣的。