反应详情

Benzaldehyde (101 μl) was added to a solution of 2-amino-5-[(2S)-1-[(4-fluorophenyl)sulfonyl]-2-piperidyl]-1,3,4-oxadiazole (163 mg) [see Example 32] in tetrahydrofuran (2 ml), followed by acetic acid (172 μl) and sodium triacetoxyborohydride (297 mg). The reaction mixture was stirred at room temperature for 18 hours, after which time the solvent was removed under reduced pressure and the residue partitioned between dichloromethane and saturated aqueous sodium hydrogen carbonate solution. The organic layer was separated, dried over magnesium sulphate and the solvent removed under reduced pressure. The crude product was purified by column chromatography on silica gel eluting with a solvent gradient of 0:100 changing to 40:60 (in 10% increments), by volume, ethyl acetate:hexane, to afford 2-benzylamino-5-[(2S)-1-[(4-fluorophenyl)sulfonyl]-2-piperidyl]-1,3,4-oxadiazole (6 mg) as a white solid.

1. customafter which time the solvent was removed under reduced pressure
2. customthe residue partitioned between dichloromethane and saturated aqueous sodium hydrogen carbonate solution
3. customThe organic layer was separated
4. dry with materialdried over magnesium sulphate
5. customthe solvent removed under reduced pressure
6. customThe crude product was purified by column chromatography on silica gel eluting with a solvent gradient of 0:100 changing to 40:60 (in 10% increments), by volume, ethyl acetate