Sodium hydride → HCID 12968195, compound

Participants

Reaction Steps

A solution of 2-(4-methoxyphenyl)-1-(pyrazine-2-yl)ethanone (1.0 g) and dimethylformamide-dimethylacetal (10 cm3) were stirred at room temperature for 18 h. The excess reagent was evaporated under reduced pressure to give an oil. The oil was dissolved in tetrahydrofuran (60 cm3). N-methyl 2-(4-methylthiazol-2-yl)acetamide (0.74 g) and methanol (0.36 cm3) were added followed by sodium hydride (0.42 g). The reaction mixture was stirred at room temperature under nitrogen for 18 h then poured into water (500 cm3) and extracted with diethyl ether (3×150 cm3). The ether extracts were combined, washed with brine dried over magnesium sulphate, filtered and evaporated under reduced pressure to give an oil. The oil was purified by chromatography using dichloromethane (500 cm3), dichloromethane/methanol (99:1, 500 cm3) dichloromethane/methanol (98:2) as eluant. The appropriate fractions were combined and evaporated under reduced pressure to give a foam, which on tritiation with ether gave a solid. The solid was recrystallised from ethyl acetate to give 5-(4-methoxyphenyl)-1-methyl -3-(4-methylthiazol-2-yl)-6-(pyrazin-2-yl)-1H-pyridin-2-one (0.15 g 8%) as a greenish-yellow solid m.p. 168-170° C. (Found: C, 64.48; H, 4.45; N, 14.22. C21H18N4O2S requires C, 64.60; H, 4.65; N, 14.35%); δH (360 MHz; CDCl3) 2.52 (3H, s, ArCH3) 3.53 (3H, s, NMe), 3.74 (3H, s, OCH3) 6.70(2H, d, J 9, methoxyphenyl H-2), 6.92(2H, d, J 9, methoxyphenyl H-2), 7.05 (1H, s, thiazolyl H-4) 8.25 (1H, d, J pyrazine H-), 8.52 (1H, d, J pyrazine H-) 8.72 (2H d J pyrazine H- and 1H, s, pyridone H-4); m/z (ESP+) 391 (MH+).

Provenance & Evidence