反应详情

In 300 ml of chloroform was dissolved 33.7 g (0.22 mole) of N-methyl-L-alanine methyl ester.hydrochloride, followed by the addition of 65 ml of acetic anhydride and 110 ml of triethylamine. The mixture was allowed to stand at room temperature for 24 hours and, after the excess acetic anhydride was decomposed with water, was neutralized with sodium hydrogen carbonate. The chloroform layer was separated, the water layer was extracted with ethyl acetate (120 ml×5), and the chloroform and ethyl acetate layers were combined and concentrated under reduced pressure. The brown oil thus obtained was dissolved in chloroform, washed with aqueous sodium hydrogen carbonate and concentrated under reduced pressure. By the above procedure there was obtained 31.8 g of N-acetyl-N-methyl-L-alanine methyl ester as brown oil.

1. customThe chloroform layer was separated
2. extractionthe water layer was extracted with ethyl acetate (120 ml×5)
3. concentrationconcentrated under reduced pressure
4. customThe brown oil thus obtained
5. washwashed with aqueous sodium hydrogen carbonate
6. concentrationconcentrated under reduced pressure