4,5-二氢-3-甲基-1-(4-氯-2-氟苯基)-4-二氟甲基-1,2,4-三唑-5(1H)酮的合成工艺研究

摘要

4, 5-Dihydro-3-methyl-l-(4-chloro-2-fluorophenyl)-4-difluoromethyl-l, 2, 4-triazol-5-( 1H)-one was synthesized by the N-alkylation of the potassium salt of 4,5-dihydro-3-methyl-l-(4-chloro-2-fluorophenyl)-l,2,4-triazol-5(lH)-one with chlorodifluoromethane at 165 *C. The yield of the product was above 56 % and the purity was above 95%. The effect of raw materials, amounts of alkali, reaction temperature on the yield of N-alkylation was investigated. The optimal reaction conditions were found as follows: w(potassium salt) '? W(K2CO3) = l ! 2,m(potassium salt) '? M(NMP)=l ? 5.%以4,5-二氢-3-甲基-1-(4-氯-2-氟苯基)-1,2,4-三唑-5(1H)酮的钾盐为原料,与一氯二氟甲烷进行N-烷基化反应合成了4,5-二氢-3-甲基-1-(4-氯-2-氟苯基)-4-二氟甲基-1,2,4-三唑-5(1H)酮.研究了不同原料、碱性试剂用量、反应温度等因素对反应收率的影响,实验结果表明,最佳工艺条件为:n(钾盐)∶n(碳酸钾)=1∶2,m(钾盐)；m(N-甲基吡咯烷酮)=1∶5,反应温度165℃,在此条件下,产物收率≥56％,质量分数≥95％.