反应详情

温度

5 °C

A solution of boron tribromide (3.1 mL, 1 M in DCM) was added drop-wise to a 100 mL round bottomed flask containing ethyl 3-(1-(4-bromobenzyl)-6-methoxy-1H-benzo[d]imidazol-2-yl)-2,2-dimethylpropanoate (700 mg, 1.6 mmol) and DCM (30 mL) at −78° Celsius. The resulting solution was allowed to warm to 5° Celsius over 3 h and partitioned with sat. NaHCO3 (50 mL). The aqueous layer was extracted with DCM (3×25 mL). The combine organic layers were dried with sodium sulfate, filtered, and concentrated to dryness. The residue was subjected to FCC to give the title compound (410 mg, 60%). MS (ESI): mass calcd. for C21H23BrN2O3, 430.08; m/z found, 431.0 [M+H]+.

1. custompartitioned with sat. NaHCO3 (50 mL)
2. extractionThe aqueous layer was extracted with DCM (3×25 mL)
3. dry with materialThe combine organic layers were dried with sodium sulfate
4. filtrationfiltered
5. concentrationconcentrated to dryness