[CH3:1][C:2]1[N:3]([C:13]2[CH:18]=[CH:17][CH:16]=[C:15]([C:19]([F:22])([F:21])[F:20])[CH:14]=2)[C:4](=[O:12])[C:5]([C:8]([O:10][CH3:11])=[O:9])=[N:6][CH:7]=1.[Br:23]N1C(=O)CCC1=O.O>CN(C=O)C>[Br:23][C:7]1[N:6]=[C:5]([C:8]([O:10][CH3:11])=[O:9])[C:4](=[O:12])[N:3]([C:13]2[CH:18]=[CH:17][CH:16]=[C:15]([C:19]([F:22])([F:20])[F:21])[CH:14]=2)[C:2]=1[CH3:1]Methyl 5-methyl-3-oxo-4-[3-(trifluoromethyl)phenyl]-3,4-dihydropyrazine-2-carboxylate (400 g, 1 eq) was dissolved in DMF (3 L) and stirred at 17-20° C. N-Bromosuccinimide (229.3 g, 1 eq) was dissolved in DMF (1 L), and added to the ester solution over 1 hour. Post-addition, the reaction was stirred at 17-20° C. for 10 hours. The reaction mixture was added to water (15 L) with stirring. The resulting slurry was stirred at 20-25° C. overnight. The title compound was collected by filtration. The cake was washed with water (1 L) and heptane (1 L) and then dried to constant weight at 40° C. to give 456 g (91%).
Wird geladen…
