反应详情

To a stirring solution of 4-iodo-1H-benzimidazole (1.00 g, 4.1 mmol) in DMF (12 mL) was added sodium hydride (180 mg of a 60% dispersion in mineral oil; 4.5 mmol), and the resulting mixture was stirred at room temperature under nitrogen for 50 minutes. 2-(Trimethylsilyl)ethoxymethyl chloride (870 μL, 4.92 mmol) was added dropwise over 5 minutes at room temperature, then the mixture was stirred overnight. Water (50 mL) was added, and the mixture was washed with ethyl acetate (3×25 mL). The combined organic layers were washed with water (2×30 mL), then with saturated sodium chloride solution (30 mL), then dried (MgSO4) and concentrated in vacuo. The crude product was purified by flash chromatography on silica gel, eluting with 0 to 20% ethyl acetate in dichloromethane, affording the product as a white solid (1.20 g, 78%). 1H NMR (400 MHz, CDCl3): δ 8.05 (1H, s), 7.74 (1H, dd, J=0.6, 7.5 Hz), 7.52 (1H, t, J=4.2 Hz), 7.09 (1H, t, J=7.9 Hz), 5.51 (2H, s), 3.50 (2H, t, J=8.2 Hz), 0.90 (2H, dd, J=8.3, 16.4 Hz), −0.05 (9H, s); m/z (ES+) 375 [MH+].

1. stirringthe mixture was stirred overnight
2. washthe mixture was washed with ethyl acetate (3×25 mL)
3. washThe combined organic layers were washed with water (2×30 mL)
4. dry with materialwith saturated sodium chloride solution (30 mL), then dried (MgSO4)
5. concentrationconcentrated in vacuo
6. customThe crude product was purified by flash chromatography on silica gel
7. washeluting with 0 to 20% ethyl acetate in dichloromethane