反应详情

温度

-70 °C

Combine 3-pyridineacetonitrile (25 g, 212 mmol) and tetrahydrofuran (200 mL). Cool to about −70° C . using a dry-ice/acetone bath. Add dropwise, a solution of sodium bis(trimethylsilyl)amide (435 mL, 1 M in tetrahydrofuran, 435 mmol) while maintaining the reaction temperature below about −68° C. When the addition is complete, warm the reaction mixture to ambient temperature and allow to stir for 1 hour. Transfer the above solution via cannula into a cooled (−5° C.) solution of ethyl bromoacetate (84.5 mL, 762 mmol) in tetrahydrofuran (500 mL) at such a rate that the temperature of the reaction mixture does not rise above about 15° C. Allow to stir at ambient temperature. After 18 hours, quench with saturated aqueous solution of ammonium chloride and evaporate in vacuo to remove most of the tetrahydrofuran. Extract the evaporated reaction mixture twice with diethyl ether. Dry the organic layer over MgSO4, filter, and concentrate in vacuo to obtain a residue. Chromatograph the residue on silica gel eluting with 1/1 ethyl acetate/hexane to give the title compound.

1. additionAdd dropwise
2. additionWhen the addition
3. temperaturewarm the reaction mixture to ambient temperature
4. customdoes not rise above about 15° C
5. stirringto stir at ambient temperature
6. waitAfter 18 hours
7. customquench with saturated aqueous solution of ammonium chloride
8. customevaporate in vacuo
9. customto remove most of the tetrahydrofuran
10. extractionExtract
11. customthe evaporated reaction mixture twice with diethyl ether
12. dry with materialDry the organic layer over MgSO4
13. filtrationfilter
14. concentrationconcentrate in vacuo
15. customto obtain a residue