反应详情

To a stirred solution of the material from Step 5 (8 g, 18.11 mmol) in a 2:1 mixture of chloroform and saturated aqueous NaHCO3 (271 mL) was added benzyl chloroformate (2.59 mL, 118.11 mmol). The reaction mixture was stirred at room temperature for 1 hour, partitioned and extracted with chloroform. The combined organics were washed with brine, dried over MgSO4, filtered and concentrated in vacuo. The residue was purified by flash chromatography on silica gel using EtOAc-hexanes (10 to 70%) to yield 7 g of the title compound. LCMS (M+1)=576

1. custompartitioned
2. extractionextracted with chloroform
3. washThe combined organics were washed with brine
4. dry with materialdried over MgSO4
5. filtrationfiltered
6. concentrationconcentrated in vacuo
7. customThe residue was purified by flash chromatography on silica gel