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第 48 卷第 2 期Vol. 48 No. 2
2018 年 4 月Apr 2018

所屬欄目:農藥及中間體

一鍋法合成3-二氟甲基-1-甲基-1H-吡唑-4-羧酸
杜升華1,2,劉 源1,2,王艷麗1,2 (1. 湖南化工研究院 國家農藥創(chuàng )制工程技術(shù)研究中心,湖南 長(cháng)沙 410014;2. 農用化學(xué)品湖南省重點(diǎn)實(shí)驗室,湖南 長(cháng)沙 410014)
摘 要:以4,4-二氟乙酰乙酸乙酯、原甲酸三乙酯、甲基肼為原料,采用一鍋法合成了重要農藥中間體3-二氟甲基-1-甲基-1H-吡唑-4-羧酸。并對反應條件進(jìn)行了優(yōu)化,反應總收率大于74%,產(chǎn)品含量大于98%。該方法具有工藝條件溫和、易操作、三廢少等優(yōu)點(diǎn),且生產(chǎn)成本較低,產(chǎn)品品質(zhì)好,含量高,適合大規模工業(yè)化清潔生產(chǎn)。
關(guān)鍵詞:一鍋法;農藥中間體;工藝改進(jìn)
中圖分類(lèi)號:S482.2  文獻標識碼:A  文章編號:1009-9212(2018)02-0027-03
An One-pot Process for the Synthesis of 3-(Difluoromethyl)-1-methyl-1H-pyrazole-4-carboxylic Acid
DU Shen-hua1,2, LIU Yuan1,2, WANG Yan-li1,2 (1. Hunan Research Institute of Chemical Industry Co., Ltd., National Engineering Research Centre for Agrochemicals, Changsha 410014, China; 2. Hunan Province Key Laboratory for Agrochemicals, Changsha 410014, China)
Abstract:An important pesticide intermediates 3-(difluoromethyl)-1-methyl-1H-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 over 98% 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.
Key words:one-pot; pesticide intermediates; process improvement
作者簡(jiǎn)介:杜升華(1976-),男,湖南新化人,副研究員,碩士,研究方向:農藥及精細化學(xué)品的合成與開(kāi)發(fā)(E-mail:48407849@qq.com)。
收稿日期:2018-03-28
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