Water → HCID 54442301, compound

Participants

Reaction Conditions

Reaction Steps

N,N-Carbonylimidazole (14.86 g) was added to a slurry of pyrazine-2-carboxylic acid in dry dimethylformamide (100 cm3). After stirring for one hour 4-methoxyphenylacetic acid t-butyl ester (10.8 g) was added. The reaction mixture was cooled to −30° C. then sodium hydride (4.62 g) was added. The reaction mixture was stirred at −30° C. for 1h then allowed to warm to room temperature overnight. The reaction mixture was poured into water and acidified to pH 8 with acetic acid. The solution was extracted with ether (3×250 cm3). The ether extracts were combined, washed with brine, dried over magnesium sulphate filtered and evaporated under reduced pressure to give a solid. The solid was purified by chromatography using ethyl acetate/hexane (1:1) as eluant. The appropriate fractions were combined and evaporated under reduced pressure to give 2-(4-methoxyphenyl)-3-oxo-3-pyrazine-2-yl propionic acid t-butyl ester as a solid (9.8 g 61%) δH (250 MHz; CDCl3) 1.39 (9 H, s, C(CH3)3), 3.70 (3 H, s, OCH3), 5.87(1 H, s, tBuO2CCH), 6.90 (2H, d, J 9 Hz, methoxyphenyl H-2) 7.32 (2H, d, J 9 Hz, methoxyphenyl H-3) 8.66 (1H, dd pyrazine H-) 8.74 (1H, d pyrazine H-) 9.25 (1H, d pyrazine H-)

Provenance & Evidence