反应详情

In this Example, 1-(2,6-difluorobenzyl)-4-methylbenzimidazole (49) was prepared according to Method D. To 1-(2,6-difluorobenzyl)-2-hydroxymethyl-4-methylbenzimidazole (Example 40) (1.82 g, 4.52 mmol) dissolved in 1.5 M H2SO4 (40 mL) was added KMnO4 (1.50 g, 9.49 mmol, 160 M%). After 1 h at room temperature, the reaction mixture was filtered and washed with water. The brown solid was collected, suspended in acetone/methanol and filtered. The filtrate was collected and purified by flash chromatography eluting with 10% MeOH/CH2Cl2 increasing to 50% MeOH/CH2Cl2 to produce 1.42 g (4.70 mmol, 80% yield) of white powder. 1H-NMR (200 MHz, CD2Cl2): δ7.99 (br s, 1H, H2), 7.37 (br d, J=7.9 Hz, 1H, H7), 7.32 (m, 1H, H4″), 7.17 (dd, J=7.3, 7.9 Hz, 1H, H6), 7.03 (d, J=3.2 Hz, 1H, H5), 6.96 (m, 2H, H3″,5″,), 5.40 (s, 2H, CH2PhF2), 2.59 (s, 3H, CH3).

1. filtrationthe reaction mixture was filtered
2. washwashed with water
3. customThe brown solid was collected
4. filtrationfiltered
5. customThe filtrate was collected
6. custompurified by flash chromatography
7. washeluting with 10% MeOH/CH2Cl2 increasing to 50% MeOH/CH2Cl2