反应详情

温度

0 °C

5-[2-(2-Chloro-5-methoxy-phenyl)-1-hydroxy-1-trifluoromethyl-propyl]-3-methyl-3H-benzooxazol-2-one (34 mg, obtained in Example 192, step 3) was dissolved in CH2Cl2 (5 mL) and cooled to 0° C. Borontribromide (1M in CH2Cl2, 0.33 mL) was added over a period of 10 minutes. Stirring was continued for 1 hour at 0° C. The reaction mixture was poured into ice and basified with sat. NaHCO3 and extracted three times with CH2Cl2. The combined organic layers were washed with brine, dried over Na2SO4, filtered and the solvent was evaporated. The residue was purified by flash chromatography (silica gel, heptane:ethyl acetate=6:4) to give the title compound as a colorless amorphous foam (22 mg, 67%). MS (neg. ion, m/e)=400.1 [(M−H)−].

1. extractionextracted three times with CH2Cl2
2. washThe combined organic layers were washed with brine
3. dry with materialdried over Na2SO4
4. filtrationfiltered
5. customthe solvent was evaporated
6. customThe residue was purified by flash chromatography (silica gel, heptane:ethyl acetate=6:4)