反应详情

温度

65 °C

The mixture of regioisomers from step 2 {[(S)-1-(2-amino-4-iodo-phenylcarbamoyl)-2-phenyl-ethyl]-carbamic acid tert-butyl ester and [(S)-1-(2-amino-5-iodo-phenylcarbamoyl)-2-phenyl-ethyl]-carbamic acid tert-butyl ester} (1.0 g, 2.08 mmol) were dissolved in glacial acetic acid (30 mL) and heated to 65° C. for 1 hour. The reaction was cooled, concentrated in vacuo, basified with 10% w/v aqueous sodium hydrogen carbonate solution and extracted with ethyl acetate (2×20 mL). The organic extracts were combined, washed with brine, dried over sodium sulfate, filtered and concentrated in vacuo. The crude product was purified by chromatography over silica gel eluted with 20% v/v ethyl acetate/hexanes to give [(S)-1-(5-iodo-1H-benzoimidazol-2-yl)-2-phenyl-ethyl]-carbamic acid tert-butyl ester as a mixture of tautomers (950 mg, 99%).

1. temperatureThe reaction was cooled
2. concentrationconcentrated in vacuo
3. extractionextracted with ethyl acetate (2×20 mL)
4. washwashed with brine
5. dry with materialdried over sodium sulfate
6. filtrationfiltered
7. concentrationconcentrated in vacuo
8. customThe crude product was purified by chromatography over silica gel
9. washeluted with 20% v/v ethyl acetate/hexanes