Cesium carbonate → 4-({2-[4-(5-Chloro-2-cyanophenyl)-5-methoxy-2-oxopyridin-1(2H)-yl]butanoyl}amino)-2,6-difluorobenzoic acid

Participants

Reaction Conditions

Reaction Steps

67 mg (0.20 mmol, 2 eq.) of caesium carbonate were added to a solution of 53 mg (0.10 mmol) of methyl 4-({2-[4-(5-chloro-2-cyanophenyl)-5-methoxy-2-oxopyridin-1(2H)-yl]butanoyl}amino)-2,6-difluorobenzoate (racemate) in 1.25 ml of a mixture of methanol/water (4/1), and the resulting suspension was stirred at 60° C. for 1 h. Methanol was removed at 30° C. under reduced pressure. The reaction mixture was cooled to RT and adjusted to pH 3 using aqueous hydrochloric acid (1N). The aqueous phase was extracted with ethyl acetate. The combined organic phases were dried (sodium sulphate), filtered and concentrated under reduced pressure. The crude product was purified by preparative HPLC (water/acetonitrile/0.1% formic acid gradient). Yield: 11 mg (21% of theory)

Provenance & Evidence