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第 38 卷第 4 期Vol. 38 No. 4
2008 年 8 月Aug 2008

所屬欄目:農藥及中間體

高效除草劑雙草醚中間體2,6-雙(4,6-二甲氧嘧啶氧基)苯甲酸的合成
李元祥1,2 (1. 湖南懷化學(xué)院 化學(xué)化工系,湖南 懷化 418008;2. 華中師范大學(xué) 化學(xué)學(xué)院農藥與化學(xué)生物學(xué)教育部重點(diǎn)實(shí)驗室,湖北 武漢 430079)
摘 要:以2,6-二羥基苯甲酸為原料,與無(wú)水甲醇在濃硫酸或三氟化硼-乙醚的催化下制備2,6-二羥基苯甲酸甲酯,收率分別為43.5%、46%;2,6-二羥基苯甲酸甲酯再與4,6-二甲氧基-2-甲磺酰嘧啶(DMSP)在碳酸鉀丙酮條件下反應生成2,6-雙(4,6-二甲氧嘧啶氧基)苯甲酸甲酯,收率91.5%;所得中間體經(jīng)20%的氫氧化鉀水溶液水解后由0.7%的檸檬酸酸化后生成2,6-雙(4,6-二甲氧嘧啶氧基)苯甲酸,收率72%。
關(guān)鍵詞:除草劑;雙草醚;中間體;合成
中圖分類(lèi)號:TQ457.29  文獻標識碼:A  文章編號:1009-9212(2008)04- 0021-04
Synthesis of Intermediate 2,6-Bis(4,6-dimethoxypyrimidin-2-yloxy)benzoate for Herbicide Bispyribac-sodium
LI Yuan-xiang1,2 (1. Chemistry and Chemical Engineering Department,Huaihua University,Huaihua 418008,China;2. Key Laboratory of Pesticide & Chemical Biology,Ministry of Education,College of Chemistry,Central China Normal University,Wuhan 430079,China)
Abstract:Methyl 2,6-dihydroxybenzoate was first synthesized with 2,6-dihydroxybenzoic acid as the raw materials through reaction of absolute methanol in the presence of the strong sulfuric acid or BF3·Et2O,the yield was 43.5% and 46% respectively. Then methyl 2,6-bis(4,6-dimethoxy-pyrimidin-2-yloxy)benzoate was synthesized from methyl 2,6-dihydroxy-benzoate and 4,6-dimethoxy-2-(methylsulfonyl)pyrimidine(DMSP) in the presence of K2CO3 in acetone,and the yield was 91.5%. The previous intermediate can be formed 2,6-bis(4,6-dimeth-oxypyrimidin-2-yloxy)benzoic acid via hydrolyzation with the 20% KOH and acidification with the 0.7 % citric acid,and the yield was 72%.
Key words:herbicide;bispyribac-sodium;intermediates;synthesis
作者簡(jiǎn)介:李元祥(1968-),男,湖南懷化人,講師,博士,主要從事新型農藥分子的設計與合成。(E-mail:liyuanjun68@yahoo.com.cn)
收稿日期:2008-08-04
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