Ethyl 6-methylpyridazine-3-carboxylate is an organic synthesis intermediate and a pharmaceutical intermediate, which can be used in laboratory organic synthesis processes and chemical and pharmaceutical research and development. Existing methods for preparing ethyl 6-methylpyridazine-3-carboxylate include biosynthesis, electrochemical synthesis, and chemical synthesis.
1 kg of 5-methyl pyrazine-2-carboxylic acid crude with 10 liters of anhydrous butanone heated reflux 1.5h, cooled for a few moments, add 15 grams of activated charcoal and then heated reflux 0.6h, hot filtration, filtrate concentrated to 30% under reduced pressure, the concentrate cooled precipitated crystals, pumping and drying to obtain 875.8 g of 6-methyl pyridazine-3-carboxylic acid ethyl ester, purity of 99.6%, refining yield of 92.2%. The distillate butanone 6.5 liters can be used as extractant for the extraction process of post-treatment in the production of ethyl 6-methylpyridazine-3-carboxylate. Among them, the content of 5-methylpyrazine-2-carboxylic acid in the crude product was 95.2% by mass.
