反应详情

温度

0 °C

To a stirred solution of 2-hydroxy-4-nitrobenzonitrile (5.0 g, 30.48 mmol) in DMF (25 mL) was added Cs2CO3 (14.89 g, 45.7 mmol). The mixture was cooled to 0° C., and tert-butyl (2-bromoethyl)carbamate (7.17 g, 32 mmol) was added at rt. The reaction mixture was stirred for 12 h at 90° C. under nitrogen. The reaction mixture was cooled to rt and DMF was removed in vacuo. The residue was treated with ethyl acetate (50 mL) and washed with brine (30 mL). The organic layer was dried over anhydrous sodium sulphate and concentrated in vacuo. The residue was taken up in dichloromethane (10 mL) and silica (5 g). The resultant slurry of the compound on silica was subjected to flash chromatography using a Teledyne Isco instrument (40 g RediSep silica column, 50% ethyl acetate in pet-ether) to get tert-butyl (2-(2-cyano-5-nitrophenoxy)ethyl)carbamate (4 g, 42.7%) as a yellow solid. 1H NMR (400 MHz, CDCl3) δ ppm 7.90 (1H, d, J=8.4 Hz), 7.82 (1H, s), 7.76 (1H, d, J=8.4 Hz), 5.04 (1H, br s), 4.27-4.24 (2H, m), 3.66-3.60 (2H, m), 1.45 (9H, s).

1. temperatureThe reaction mixture was cooled to rt
2. customDMF was removed in vacuo
3. additionThe residue was treated with ethyl acetate (50 mL)
4. washwashed with brine (30 mL)
5. dry with materialThe organic layer was dried over anhydrous sodium sulphate
6. concentrationconcentrated in vacuo