Acetic Anhydride → N-acetyl-N-methyl-L-alanine methyl ester

Participants

Reaction Steps

In 300 ml of chloroform was dissolved 33.7g (0.22 mol) of N-methyl-L-alanine methyl ester hydrochloride, followed by 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, the solution was neutralized with sodium bicarbonate. The chloroform layer was separated and the water layer was extracted with ethyl acetate (120 ml × 5). The chloroform and ethyl acetate layers were combined and concentrated under reduced pressure. The brown-colored oily residue was dissolved in chloroform and washed with an aqueous solution of sodium hydrogen carbonate, followed by concentration under reduced pressure. By the above procedure was obtained 31.8 g of N-acetyl-N-methyl-L-alanine methyl ester.

Provenance & Evidence