目的 对西格列汀的合成工艺进行改进。方法 以2，4，5-三氟苯乙酸为原料，经亲核取代、环化、氢化、NaBH4还原反应，并进行拆分优化。结果 制得的西格列汀光学纯度高于98%、总收率36%。结论 拆分方法具有操作简便、生产成本低、反应条件温和的优点，适用于西格列汀的工业化应用。

Objective To study the improved method for synthesis of sitagliptin. Methods 2,4,5-Trifluoro phenyl acetic acid was used as raw material to synthesize the target compound by nucleophilic substitution, cyclization, hydrogenation, and NaBH4 reduction. And isomer resolution was optimized. Results After optimization, sitagliptin with optical purity of 99.7% was obtained. The total recovery of the synthetic route was 36%. Conclusion The resolution method with advantages of easy-operation, low production cost, and mild reaction conditions is suitable for industrial application of sitagliptin.