一锅法合成3-二氟甲基-1-甲基-1H-吡唑-4-羧酸

An One-pot Process for the Synthesis of 3-(Difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylic Acid

以4,4-二氟乙酰乙酸乙酯、原甲酸三乙酯、甲基肼为原料,采用一锅法合成了重要农药中间体3-二氟甲基-1-甲基-1H-吡唑-4-羧酸。并对反应条件进行了优化,反应总收率大于74%,产品含量大于98%。该方法具有工艺条件温和、易操作、三废少等优点,且生产成本较低,产品品质好,含量高,适合大规模工业化清洁生产。

An important pesticide intermediates 3-（difluoromethyl）-1-methyl-1 H-pyrazole-4-carboxylic acid was synthesized by an one-pot method using ethyl 4,4-difluoro-3-oxobutanoate, triethyl orthoformate and methylhydrazineas as the raw materials. Under optimal reaction conditions, a yield of over 74% and a purity of over98% were obtained. The method was suitable for industrial production with many advantages including mild reaction conditions, simple operation, less waste, low production cost and high quality.