反应详情

The crude N-acetoacetyl-L-aspartyl-L-phenylalanine methyl ester was dissolved in 100 parts by volume of water and 11.7 parts by volume of acetic acid. Toluene 200 parts by volume and 6.95 parts of hydroxylamine hydrochloride were added and the mixture stirred for 2.5 hours. The aqueous layer was separated and cooled to 0°-5° C. 15 parts by volume concentrated hydrochloric acid were added and the resulting mixture was cooled at 0°-5° C. overnight. The precipitate was collected on a filter and air dried for 3 hours to give 26.4 parts of α-L-aspartyl-L-phenylalanine methyl ester hydrochloride dihydrate.

1. customThe aqueous layer was separated
2. temperaturecooled to 0°-5° C
3. addition15 parts by volume concentrated hydrochloric acid were added
4. temperaturethe resulting mixture was cooled at 0°-5° C. overnight
5. customThe precipitate was collected on
6. filtrationa filter
7. customair dried for 3 hours