反应详情

温度

0 °C

Sodium hydride (7.2 g of a 60% dispersion, 0.188 mol) was placed in a flask and washed three times with hexane. The resulting solid was suspended in DMF (140 mL) and cooled to 0° C. Trimethyl phosphonoacetate (30.7 mL, 0.190 mol) was added dropwise to this suspension to give a clear homogeneous solution. After stirring for another 20 minutes at 0° C., a solution of benzyl 3-fluoro-4-formylphenylcarbamate (2) (48 g, 0.176 mol) in DMF (140 mL) was added dropwise. The resulting orange suspension was allowed to warm slowly to room temperature and stirred for 16 hours. The reaction mixture was poured into 0.5 N HCl (1.5 L) and extracted with three 300 mL portions of dichloromethane. Combined organic phases were washed with saturated NaHCO3, twice with H2O, brine, and dried (Na2SO4). While concentrating the solution on a rotary evaporator, the product precipitated from solution and these solids were collected on a filter (33.4 g). The filtrate was concentrated to give more solids that were washed with ether (additional 8.4 g obtained).

1. washwashed three times with hexane
2. customto give a clear homogeneous solution
3. temperatureto warm slowly to room temperature
4. stirringstirred for 16 hours
5. extractionextracted with three 300 mL portions of dichloromethane
6. washCombined organic phases were washed with saturated NaHCO3, twice with H2O, brine
7. dry with materialdried (Na2SO4)
8. concentrationWhile concentrating the solution
9. customon a rotary evaporator
10. customthe product precipitated from solution
11. customthese solids were collected on
12. filtrationa filter (33.4 g)
13. concentrationThe filtrate was concentrated
14. customto give more solids that
15. washwere washed with ether (additional 8.4 g obtained)