反应详情

To a suspension of the product from Example 25B (0.76 g, 2.5 mmol) in tetrahydrofuran (40 mL) was added a solution of potassium t-butoxide (1.0 M in tetrahydrofuran, 2.6 mL, 2.6 mmol). After stirring for 30 minutes at room temperature a pale yellow homogeneous solution resulted. To the reaction was added ethyl bromoacetate (0.42 g, 2.5 mmol) and stirring was continued overnight at room temperature. The reaction was concentrated, diluted with ethyl acetate (100 mL), washed with water and brine, dried over MgSO4, filtered and concentrated. The residue was dissolved in minimal amount of dichloromethane and loaded onto a silica gel column. The product was eluted with a gradient of 5% ethyl acetate/hexanes to 50% ethyl acetate/hexanes to afford the title compound.

1. customresulted
2. stirringstirring
3. waitwas continued overnight at room temperature
4. concentrationThe reaction was concentrated
5. additiondiluted with ethyl acetate (100 mL)
6. washwashed with water and brine
7. dry with materialdried over MgSO4
8. filtrationfiltered
9. concentrationconcentrated
10. dissolutionThe residue was dissolved in minimal amount of dichloromethane
11. washThe product was eluted with a gradient of 5% ethyl acetate/hexanes to 50% ethyl acetate/hexanes