反应详情

A solution of 2-amino-4-chlorophenol (14.3 g, 100 mmol), tert-butyldimethylsilyl chloride (18 g, 120 mmol) and imidazole (14 g, 200 mmol) in DMF (250 mL) was stirred at room temperature for 24 hours, concentrated, and partitioned between brine (300 mL) and ethyl acetate (300 mL). The aqueous phase was extracted with ethyl acetate. The combined phases were dried (MgSO4), filtered, and concentrated. The concentrate was purified by flash column chromatography on silica gel with 15% ethyl acetate/hexanes to provide 18.5 g (71.7% )of the desired product. MS (DCI/NH3) m/z 258 (M+H)+; 1H NMR (300 MHz, CDCl3) δ 6.70 (d, J=2.71 Hz, 1H), 6.64 (d, J=8.5 Hz, 1H), 6.57 (dd, J=2.7 and 8.5 Hz, 1H), 3.75 (br s, 2H), 1.01 (s, 9H), 0.23 (s, 6H).

1. concentrationconcentrated
2. custompartitioned between brine (300 mL) and ethyl acetate (300 mL)
3. extractionThe aqueous phase was extracted with ethyl acetate
4. dry with materialThe combined phases were dried (MgSO4)
5. filtrationfiltered
6. concentrationconcentrated
7. customThe concentrate was purified by flash column chromatography on silica gel with 15% ethyl acetate/hexanes