反应详情

A solution of 2-acetylamino-5-(1-hydroxy-ethyl)-4-trifluoromethyl-benzoic acid methyl ester (600 mg, 1.97 mmol) and Et3N (412 μL, 3.0 mmol) in DCM (6 mL) was cooled to 0° C. and treated with methanesulfonyl chloride (194 μL, 2.46 mmol) dropwise. The mixture was allowed to warm to r.t. and stirred for 2 h. The mixture was then diluted with DCM, and washed once with water, dried over anhydrous sodium sulfate, filtered and concentrated in vacuo to give a brown oil which was taken up in MeOH. This solution was allowed to stand for 60 h at r.t. The mixture was then concentrated in vacuo and the crude product was purified by column chromatography (silica gel 60, hexanes/EtOAc 5:1) to give 2-amino-5-(1-methoxy-ethyl)-4-trifluoromethyl-benzoic acid methyl ester (196 mg, 0.71 mmol, 36%) as a white powder, m.p. 112-114° C., ESI-MS: m/z 278 [M+H]+.

1. washwashed once with water
2. dry with materialdried over anhydrous sodium sulfate
3. filtrationfiltered
4. concentrationconcentrated in vacuo
5. customto give a brown oil which
6. waitto stand for 60 h at r.t
7. concentrationThe mixture was then concentrated in vacuo
8. customthe crude product was purified by column chromatography (silica gel 60, hexanes/EtOAc 5:1)