3-Cyclopentylpropionyl chloride → 3-cyclopentyl-N-(2,2-dimethyl-4-oxo-4H-1,3-benzodioxin-7-yl)propanamide

Participants

Reaction Conditions

Reaction Steps

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).

Provenance & Evidence