Trifluoromethanesulfonic acid → 3-(3-bromo-2-methylphenyl)pyrimidine-2,4(1H,3H)-dione
Reaction equation
[Br:1][C:2]1[C:3]([CH3:25])=[C:4]([N:8]2[C:13](=[O:14])[CH:12]=[CH:11][N:10](CC3C=CC(OC)=CC=3)[C:9]2=[O:24])[CH:5]=[CH:6][CH:7]=1.FC(F)(F)S(O)(=O)=O>C(O)(C(F)(F)F)=O>[Br:1][C:2]1[C:3]([CH3:25])=[C:4]([N:8]2[C:13](=[O:14])[CH:12]=[CH:11][NH:10][C:9]2=[O:24])[CH:5]=[CH:6][CH:7]=1Participants
4
Procedure
A solution of 3-(3-bromo-2-methylphenyl)-1-(4-methoxybenzyl)pyrimidine-2,4(1H,3H)-dione (0.87 g, 2.17 mmol) in TFA (5.5 mL) was treated with trifluoromethanesulfonic acid (0.55 mL) and the mixture was stirred at room temperature overnight. The mixture was slowly poured onto ice and stirred while warming to room temperature. The precipitate was collected by filtration, washed with water and dried to provide 3-(3-bromo-2-methylphenyl)pyrimidine-2,4(1H,3H)-dione as a purple solid (0.62 g, 96% yield). Mass spectrum m/z 281, 283 (M+H)+. 1H NMR (400 MHz, DMSO-d6) δ 11.36 (d, J=4.4 Hz, 1H), 7.67 (dd, J=6.5, 2.8 Hz, 1H), 7.60 (dd, J=7.7, 5.9 Hz, 1H), 7.27-7.21 (m, 2H), 5.72 (dd, J=7.7, 1.3 Hz, 1H), 2.07 (s, 3H).