反应详情

5.0 Parts of D-phenylalanine methyl ester, dissolved in 80 parts of methanol, is treated, at room temperature, with 0.90 part of sodium methoxide. The mixture is heated rapidly to reflux and maintained at reflux for about 21/21/2 hours. Then the reaction mixture is cooled, acidified to pH 2 with concentrated hydrochloric acid and evaporated to dryness. The remaining crystalline residue is taken up in water, and sodium carbonate is added. 1,2-Dichloroethane is added to form two phases and the mixture is shaken and filtered. The organic layer is separated, washed with saturated sodium chloride solution, dried over anhydrous magnesium sulfate and filtered. The filtrate is acidified with hydrochloric acid, cooled and stripped of solvent. Trituration with ether of the material which remains after solvent removal and subsequent filtration yields DL-phenylalanine methyl ester hydrochloride, melting at about 162°.

1. temperatureThe mixture is heated rapidly
2. temperatureto reflux
3. temperaturemaintained
4. temperatureat reflux for about 21/21/2 hours
5. temperatureThen the reaction mixture is cooled
6. customevaporated to dryness
7. additionsodium carbonate is added
8. addition1,2-Dichloroethane is added
9. customto form two phases
10. filtrationfiltered
11. customThe organic layer is separated
12. washwashed with saturated sodium chloride solution
13. dry with materialdried over anhydrous magnesium sulfate
14. filtrationfiltered
15. temperaturecooled
16. customafter solvent removal and subsequent filtration