1-Bromo-3,5-difluorobenzene → methyl 8-(1-(3,5-difluorophenyl)pyrrolidin-2-yl)-2-morpholino-4-oxo-4H-chromene-6-carboxylate

Participants

Reaction Conditions

Reaction Steps

Pd complexe (33.2 mg, 0.04 mmol) was added to a stirred mixture of methyl 2-morpholino-4-oxo-8-(pyrrolidin-2-yl)-4H-chromene-6-carboxylate (270 mg, 0.75 mmol), 1-bromo-3,5-difluorobenzene (0.095 ml, 0.83 mmol) and cesium carbonate (368 mg, 1.13 mmol) dissolved in 1,4-dioxane (5 ml). The resulting suspension was degased with argon and then stirred at 80 °C. After 18 hours, lcms showed incomplete reaction: 5% more reactants were added and heating was continued at 100 °C for 5 additionnal hours. Lcms showed ~ complete reaction after 23 hours. The reaction mixture was allowed to cool to room temperature, filtered and concentrated. The crude product was purified by flash chromatography on silica gel eluting with 0 to 6% methanol in ethyl acetate. The solvent was evaporated to dryness to afford methyl 8-(1-(3,5-difluorophenyl)pyrrolidin-2-yl)-2-morpholino-4-oxo-4H-chromene-6-carboxylate (206 mg, 58.1 %) as a clear yellow foam. LCMS and NMR are OK

Provenance & Evidence