反应详情

A mixture of 4-(4-fluorophenyl)-3-oxo-3,4-dihydropyrazine-2-carbonitrile (0.42 g, 1.95 mmol) and H2SO4 (4.16 mL, 78.1 mmol) was stirred at room temperature for 17 hours. Then the reaction mixture (amide intermediate) was added to MeOH (50 mL), and then the reaction was heated to 70° C. for 2.5 hours. The reaction mixture (methyl ester compound) was quenched with ice-water and treated with aq. 2N NaOH solution (for hydrolysis) at 0° C. The mixture was acidified with aq. 1N HCl, extracted with EtOAc, dried over MgSO4, and concentrated to afford 0.315 g (69% for 3-step process in one pot reaction) of the desired product which was rinsed with Et2O. 1H-NMR (400 MHz, DMSO-d6) δ 7.90 (d, 1H), 7.60 (m, 2H), 7.52 (d, 1H), 7.42 (t, 2H).

1. temperaturethe reaction was heated to 70° C. for 2.5 hours
2. customThe reaction mixture (methyl ester compound) was quenched with ice-water
3. additiontreated with aq. 2N NaOH solution (for hydrolysis) at 0° C
4. extractionextracted with EtOAc
5. dry with materialdried over MgSO4
6. concentrationconcentrated
7. customto afford