carbamate were selected as starting materials. The first key to successful process development was the discovery of mild chlorination conditions of 6-fluorobenzoxazolone using phosphorus pentachloride and polyphosphoric acid. The second key was the establishment of N-alkylation by the Mitsunobu reaction, which did not require excess ethyl(tert-butylsulfonyl)carbamate. In addition, kinetic study of
在这里,我们概述了 S-234462 的制造过程历史。优化工艺以6-
氟苯并恶唑酮、((1r,4r)-4-
氨基
环己基)
甲醇和(叔丁基磺酰基)
氨基甲酸乙酯为起始原料。成功工艺开发的第一个关键是发现了使用
五氯化磷和多
磷酸的 6-
氟苯并恶唑酮的温和
氯化条件。第二个关键是通过Mitsunobu反应建立N-烷基化,不需要过量的(叔丁基磺酰基)
氨基甲酸乙酯。此外,使用原位 IR 分析对 Mitsunobu 反应的动力学研究能够控制反应转化率。