反应详情

A 100 mL round bottomed flask was charged with phosphorous oxychloride (0.5 mL, 5.24 mmol) and benzene (20 mL). (2R,3S)-3-(tert-butyldimethylsilyloxy)-2-(3-chloro-4-cyano-2-methylphenylamino)-N-(2-oxo-2-phenylethyl)butanamide (1.14 g, 2.28 mmol) was then added to the mixture which was then placed under reflux for 4 h. The mixture was then concentrated en vacuo, then partitioned between EtOAc (40 mL) and a saturated solution of sodium bicarbonate (30 mL). The organic layer was washed with water (20 mL), dried (Na2SO4). Purification by flash column chromatography [hexanes/Et2O (3:2) as eluent] afforded the title compound as a white solid (30 mg, 4% yield). 1H NMR (500 MHz, CDCl3, δ in ppm) 7.59 (d, J=8 Hz, 2H), 7.32-7.42 (m, 4H), 7.28 (s, 1H), 6.58 (d, J=8 Hz, 1H), 5.17 (d, J=7 Hz, 1H), 4.93-4.95 (m, 1H), 4.66-4.75 (m, 1H), 2.40 (s, 3H) and 1.63 (d, J=6 Hz, 3H).

1. temperatureunder reflux for 4 h
2. concentrationThe mixture was then concentrated en vacuo
3. custompartitioned between EtOAc (40 mL)
4. washThe organic layer was washed with water (20 mL)
5. dry with materialdried (Na2SO4)
6. customPurification by flash column chromatography [hexanes/Et2O (3:2) as eluent]