反应详情

温度

0 °C

To a cold (0° C.) solution of 7-amino-2,2-dimethyl-4H-1,3-benzodioxine-4-one (1.93 g, 10.0 mmol) and DIEA (1.55 g, 12.00 mmol) in DCM (50 mL) was added drop-wise a solution of 3-cyclopentylpropionyl chloride (Aldrich, 1.93 g, 12.0 mmol) in DCM. The reaction was stirred at 0° C. for 1 hr, then at rt for 3 hrs. The reaction mixture was washed with an aqueous solution of HCl (1N). The organic layer was dried over MgSO4 and the solvent was removed under reduced pressure. Purification by flash chromatography on silicagel (EtOAc/c-Hex (30/70)) gave 3.05 g (96%) of the title compound as a pale yellow oil. HPLC, Rt: 4.26 min (purity: 99.6%). LC/MS, M+(ESI): 318.2, M−(ESI): 316.2. 1H NMR (CDCl3) δ: 8.13 (s, 1H), 7.82 (d, J=8.4 Hz, 1H), 7.58 (d, J=1.9 Hz, 1H), 7.05 (dd, J=1.9 Hz, J=8.4 Hz, 1H), 2.41 (t, J=7.6 Hz, 2H), 1.80-1.45 (m, 15H), 1.17-1.00 (m, 2H).

1. waitat rt for 3 hrs
2. washThe reaction mixture was washed with an aqueous solution of HCl (1N)
3. dry with materialThe organic layer was dried over MgSO4
4. customthe solvent was removed under reduced pressure
5. customPurification by flash chromatography on silicagel (EtOAc/c-Hex (30/70))