目的合成西他列汀杂质A。方法将2,4,5-三氟苯乙酸、米氏酸和3-三氟甲基-5,6,7,8-四氢-1,2,4-三唑[4,3-α]吡嗪盐酸盐以“一锅法”反应得到中间体1-{3-三氟甲基-5,6-二氢-1,2,4-三唑并[4,3-a]吡嗪-7(8H)-基}-4-(2,4,5-三氟苯基)-1,3-丁二酮,再经硼氢化钠还原得到西他列汀杂质A。结果目标化合物的结构经IR、MS和1H-NMR确证。结论该方法未见文献报道,具有成本低、操作简单、反应温和、收率高等优点。 Aim To synthesize sitagliptin impurity A Method 2,4,5-trifluorophenylacetic acid, mesaconic acid and 3-trifluoromethyl-5,6,7,8-tetrahydro-1,2,4-triazolo [4,3-a] Pyrazine hydrochloride was converted to the intermediate 1- {3-trifluoromethyl-5,6-dihydro-1,2,4-triazolo [4,3-a] Pyrazin-7 (8H) -yl} -4- (2,4,5-trifluorophenyl) -1,3-butanedione, followed by sodium borohydride reduction. Results The structures of the target compounds were confirmed by IR, MS and 1H-NMR. Conclusion This method has not been reported in the literature, which has the advantages of low cost, simple operation, mild reaction and high yield.