反応 #11703

反応方程式

(2S)-2-[(2R)-(2-tert-butoxycarbonylamino-propionyl)-(4-fluoro-benzyl)-amino]-propionic acid methyl ester

trifluoroacetic acid

→

title compound

収率 23.0%

(3R,6S)-1-(4-Fluoro-benzyl)-3,6-dimethyl-piperazine-2,5-dione

収率 23.0%

溶媒

dichloromethane

反応条件

後処理

1. 1
   温度The reaction was cooled to 0° C.
2. 2
   その他slowly quenched by addition of 3 N sodium hydroxide until basic
3. 3
   抽出The resulting mixture was extracted with dichloromethane
4. 4
   乾燥The organic layer was dried over magnesium sulfate
5. 5
   ろ過filtered
6. 6
   濃縮concentrated in vacuo

実験手順

To a solution of (2S)-2-[(2R)-(2-tert-butoxycarbonylamino-propionyl)-(4-fluoro-benzyl)-amino]-propionic acid methyl ester (43 g, 382 mmol) in dichloromethane (120 mL) at 0° C. was added trifluoroacetic acid (60 mL). The reaction was allowed to warm to ambient temperature and stirred for 2 hours. The reaction was cooled to 0° C. and slowly quenched by addition of 3 N sodium hydroxide until basic. The resulting mixture was extracted with dichloromethane. The organic layer was dried over magnesium sulfate, filtered and concentrated in vacuo to give the title compound (22 g).

出典