摘要
以氰胺和异丙醇制备异丙氧基脒甲烷磺酸盐,再与三氟乙酰乙酸乙酯反应制得2-异丙氧基-4-羟基-6-三氟甲基嘧啶,最后与(E)-2-[2-(氯甲基)苯基]-3-甲氧基丙烯酸甲酯反应合成目标嘧螨酯,通过试验考察了物料配比、反应时间、反应温度、催化剂用量等因素对反应的影响,确定了合成中较佳的试验条件:第一步反应时间12h,摩尔比为n1(三氟乙酰乙酸乙酯):n2(异丙氧基脒甲烷磺酸盐)=1.086:1,PH值为9.2时;第二步反应时间为5h,反应温度为80oC,以K2CO3作缚酸剂,DMF作溶剂,催化剂用量为2.4%。在此条件下,反应的总收率可达43%以上,原药纯度达到97.9%,且催化剂重复使用6次仍然保持较高活性。其结构经核磁、红外验证。生物活性测定结果表明该化合物具有良好的杀螨活性。
Fluacrypyrim was synthedized by reacting （E）-methyl 2-（-2-（chloromethyl）phenyl）- 3-methoxyacrylate with 2-isopropoxy-6 （trifluoromethyl）pyrimidin-4-ol prepared from ethyl 4,4,4- trifluoro-3-oxobutanoate and isopropyl carbamimidate methanesulfonate cyanamide and propan-2-ol. Through designing experiment ,the factors ,such as the mol ratio of raw materials , reaction time , reaction temperature , the dosage of catalyst , etc, were investigated to find the preferred reaction conditions . The first reaction was carried out at the mol ratio of ethyl 4,4,4-trifluoro-3-oxobutanoate and isopropyl carbamimidate methanesulfonate cyanamide was1.086：1 ,reaction time 12h, PH=9.2,while the second reaction at 80℃, K2CO3 as alkaline,DMFas solvent, the dosage of catalyst was 2.4%, reaction time was 5h. Under this conditions,the total yield of Fluacrypyrim was higher than 43%. and the purity is 97.9% The catalyst could be reused for six times without significant declining. Its structure was confirmed by 1H NMR and IR. The biological test results show that fluacrypyrim has good acaricidal activity.
