反应详情

A mixture of methyl 3-[4-[(2,4-difluorobenzyl)oxy]-2-methyl-6-oxopyrimidin-1(6H)-yl]-4-methylbenzoate (0.41 g, 0.001 mol, from Step 3) and NBS (0.2 g, 0.0011 mol) in dichloromethane (5.0 mL) is stirred at room temperature for 1.5 h under argon atmosphere. The reaction mixture is purified by flash chromatography using 30% EtOAc in hexanes to furnish the title compound (0.37 g, 75%) as a white amorphous powder: 1H NMR (CD3OD/400 MHz) δ 8.04 (d, 1H, J=1.6 Hz), 7.89 (d, 1H, J=1.6 Hz), 7.62 (m, 2H), 7.01 (m, 2H), 5.56 (s, 2H), 3.89 (s, 3H), 2.15 (s, 3H), and 2.133 (s, 3H); ES-HRMS m/z 479.0412 (M+H calcd for C21H18N2O4F2Br requires 479.0413). 19F NMR(CD3OD/400 MHz) −111.870 (m) and −115.95 (m).

1. customThe reaction mixture is purified by flash chromatography