Citric Acid → Ethyl[5-(3,5-difluorophenyl)-5-methyl-2,4-dioxo-3-pyridin-2-ylimidazolidin-1-yl]acetate

Participants

Reaction Steps

A stirred solution of ethyl[5-(3,5-difluorophenyl)-5-methyl-2,4-dioxoimidazolidin-1-yl]acetate, isomer A (100 mg, 0.320 mmol, described in Intermediate 7), 2-bromopyridine (0.156 mL, 1.60 mmol), copper powder (71.2 mg, 1.12 mmol), copper (I) chloride (6.34 mg, 0.064 mmol), and potassium acetate (94.0 mg, 0.961 mmol) in pyridine (1.8 mL) was heated at 100° C. for 18 h. The cooled reaction mixture was poured onto 10% citric acid (20 mL) and with EtOAc (3×20 mL). The combined organic extracts were dried over Na2SO4, filtered and concentrated under reduced pressure. The crude product was purified by silica gel chromatography, eluting with a gradient of hexane:EtOAc—100:0 to 50:50, to provide the title compound. MS: m/z=390 (M+1).

Provenance & Evidence