反应详情

(2R)-2-(4-Chlorobenzenesulfonylamino)-4-methylpentanoic acid amide (300 mg, 1 mmol), K2CO3 (170 mg, 1.2 mmol), and 4-methoxybenzyl chloride (170 mg, 1.1 mmol) in DMF (25 mL) was heated to 60° C. for 18 h. The reaction was then diluted with EtOAc (150 mL) and washed with H2O, brine, dried over MgSO4 and concentrated to give a crude white wax. Further purification by flash chromatography (SiO2, 25% EtOAc/hexanes) afforded the titled compound (297 mg) as a white solid in 70% yield. [α]D=+44.2 (c 1.00, MeOH); MS (ESI), (M−H)− 422.9; 1H NMR (CDCl3) δ 7.63 (d, 2H, J=7.0), 7.42 (d, 2H, J=7.0), 7.25 (d, 2H, J=8.0), 6.79 (d, 2H, J=8.0), 6.25 (br s, 1H), 5.35 (br s, 1H), 4.36 (dd, 2H, J=50, 15), 4-26 (t, 1H, J=7.2), 3.78 (s, 3H), 1.83 (m, 1H), 1.18-1.34 (m, 2H), 0.75 (d, 3H, J=7.0), 0.67 (d, 3H, J=7.0); IR (KBr) 3480, 2959, 1693, 1674, 1514, 1333, 1158 cm−1.

1. washwashed with H2O, brine
2. dry with materialdried over MgSO4
3. concentrationconcentrated
4. customto give a crude white wax
5. customFurther purification by flash chromatography (SiO2, 25% EtOAc/hexanes)