反应详情

To a suspension of hemiaminal A1 (2.6 g, 5.5 mmol) in dichloromethane (30 mL) was added triethylamine (2.3 mL, 16.4 mmol), followed by addition of methanesulfonyl chloride (0.47 g, 6.0 mmol) over 3 min. The reaction mixture was stirred for 25 min and then N-acetyl-4-aminobutyric acid (1.6 g, 10.1 mmol) added. The reaction mixture was then heated at reflux for 18 h, cooled and washed with sat. NaHCO3 (aq). The organic phase was dried over MgSO4, filtered and evaporated. The residue was further purified on silica eluting with 1:1:0.1 to 1:1:0.2 dichloromethane/ethyl acetate/methanol to give the title compound as an off white solid (1.1 g, 34%).

1. temperatureThe reaction mixture was then heated
2. temperatureat reflux for 18 h
3. temperaturecooled
4. washwashed with sat. NaHCO3 (aq)
5. dry with materialThe organic phase was dried over MgSO4
6. filtrationfiltered
7. customevaporated
8. customThe residue was further purified on silica eluting with 1:1:0.1 to 1:1:0.2 dichloromethane/ethyl acetate/methanol