反应详情

温度

0 °C

To a suspension of sodium hydride (2.6 g) in 30 ml of tetrahydrofuran, cooled to 0° C. and kept under nitrogen atmosphere, 13 ml of triethylphosphonoacetate, dissolved in 10 ml of tetrahydrofuran are added dropwise. The temperature is then brought to room temperature and the stirring is continued for 30 minutes. The mixture is again cooled to 0° C. and it is added dropwise with a solution obtained by adding portionwise to a solution of 4-piperidone monohydrate hydrochloride (10 g) in THF 2.6 g of sodium hydride, filtered to eliminate the sodium chloride which formed. At the end of the addition, the temperature is brought to room temperature and the stirring is continued for 20 hours. The solvent is then evaporated under reduced pressure and the residue is redissolved in ethyl acetate and washed with 1 N hydrochloric acid. The aqueous phase is extracted with ethyl acetate and chloroform, then it is basified to pH=9-10 by adding 20% sodium hydroxide and it is extractedb with chloroform. The aqueous phase is then salted and extracted again with chloroform three times. The pooled extracts are dried over sodium sulfate and evaporated to give 7.1 g of the product as a yellow oil.

1. additionare added dropwise
2. customis then brought to room temperature
3. temperatureThe mixture is again cooled to 0° C.
4. additionit is added dropwise with a solution
5. customobtained
6. filtrationfiltered
7. customformed
8. additionAt the end of the addition
9. customis brought to room temperature
10. waitthe stirring is continued for 20 hours
11. customThe solvent is then evaporated under reduced pressure
12. dissolutionthe residue is redissolved in ethyl acetate
13. washwashed with 1 N hydrochloric acid
14. extractionThe aqueous phase is extracted with ethyl acetate and chloroform
15. additionby adding 20% sodium hydroxide and it
16. extractionextracted again with chloroform three times
17. dry with materialThe pooled extracts are dried over sodium sulfate
18. customevaporated