反应详情

(S)-2-Ethoxy-N-(2-hydroxy-(R)-1-phenylethyl)-3-[4-(2-{4-methanesulfonyloxyphenyl}ethoxy)phenyl]propanoic amide (4.49 g; 8.59 mmole), concentrated sulfuric acid (12.5 ml), dioxan (50 ml) and water (50 ml) were stirred at 80° C. for 6 hours. After cooling, water (100 ml) was added and the product was extracted with dichloromethane (2×100 ml). The organic phases were combined and washed with brine (60 ml), dried (sodium sulfate), filtered and evaporated in vacuo. Purification by chromatography on silica gel using heptan:ethyl acetate:acetic acid (10:10:1) as gradient and azeotropic destination with toluen gave 2.78 g (yield 79%) of (S)-2-ethoxy-3-[4-(2-{4-methanesulfonyloxyphenyl} ethoxy)phenyl]propanoic acid.

1. temperatureAfter cooling
2. extractionthe product was extracted with dichloromethane (2×100 ml)
3. washwashed with brine (60 ml)
4. dry with materialdried (sodium sulfate)
5. filtrationfiltered
6. customevaporated in vacuo
7. customPurification by chromatography on silica gel