反应详情

DIPEA (51.7 mL, 296.91 mmol) was added dropwise to a stirred solution of methyl 8-bromo-2-(ethylsulfonyl)-4-oxo-4H-chromene-6-carboxylate (44.56 g, 118.77 mmol) and (R)-2-methylmorpholine hydrochloride (22.88 g, 166.27 mmol) in DCM (430 mL) at 5° C. under nitrogen. The resulting suspension was stirred at room temperature for 1 h. The reaction mixture was diluted with water and quenched slowly with HCl 1M (119 mL, 118.77 mmol) (pH 7). The phases were separated and the organic phase was washed with water, brine, dried over MgSO4 and concentrated. The crude product was triturated in EtAc for 1 h, the solid was collected by filtration and dried to afford methyl 8-bromo-2-((R)-2-methylmorpholino)-4-oxo-4H-chromene-6-carboxylate (32.6 g, 67%) as a white solid. Mass Spectrum: m/z [M+H]+=384.

1. customThe phases were separated
2. washthe organic phase was washed with water, brine
3. dry with materialdried over MgSO4
4. concentrationconcentrated
5. customThe crude product was triturated in EtAc for 1 h
6. filtrationthe solid was collected by filtration
7. customdried