反应详情

温度

0 °C

To a solution of the ester from step (a) above (4.3 g, 15.5 mol) in DMF (30 mL) was added NaH (60% in mineral oil, 0.93 g, 23.2 mmol) and the mixture was stirred at 0° C. for 1 h. MeI (1.16 mL, 18.6 mmol, Aldrich) was added drop-wise with stirring at 0° C., and the mixture was stirred at room temperature for 18 h. The reaction mixture was diluted with EtOAc (50 mL), washed with saturated solution of NH4Cl (25 mL) and brine (25 mL), dried over Na2SO4 and filtered. The solvent was removed in vacuo and the residue purified by silica gel chromatography, eluting with 10% EtOAc/hexane, to give the title compound as a light-yellow oil, which was used in the next step without additional purification. MS (ESI, pos. ion) m/z: 292 (M+1).

1. stirringwith stirring at 0° C.
2. stirringthe mixture was stirred at room temperature for 18 h
3. washwashed with saturated solution of NH4Cl (25 mL) and brine (25 mL)
4. dry with materialdried over Na2SO4
5. filtrationfiltered
6. customThe solvent was removed in vacuo
7. customthe residue purified by silica gel chromatography
8. washeluting with 10% EtOAc/hexane