反応 #8524

反応方程式

2,3,4-trifluoroaniline

methyl D-lactate

2,6-lutidine

hydrochloric acid

trifluoromethanesulfonic acid

→

title compound

収率 90.0%

Methyl (2S)-2-(2,3,4-trifluoroanilino)propionate

収率 90.0%

溶媒

dichloromethane

dichloromethane

反応条件

後処理

1. 1
   温度Under ice-cooling
2. 2
   温度Then it was cooled to 0° C. again
3. 3
   workup.STIRRINGThe mixture was stirred at the same temperature for 17 hours
4. 4
   抽出the mixture was extracted with dichloromethane
5. 5
   洗浄The extract was washed with a saturated aqueous solution of sodium chloride
6. 6
   乾燥dried over magnesium sulfate
7. 7
   ろ過filtered
8. 8
   その他After evaporating the solvent
9. 9
   その他the residue thus obtained

実験手順

Under ice-cooling, methyl D-lactate (8.5 g) and 2,6-lutidine (11.4 g) were dissolved in dichloromethane (100 ml). After dropping anhydrous trifluoromethanesulfonic acid (25.4 g), the mixture was heated to room temperature and stirred for 30 minutes. Then it was cooled to 0° C. again and a solution (30 ml) of 2,3,4-trifluoroaniline (12.0 g) in dichloromethane was dropped therein to. The mixture was stirred at the same temperature for 17 hours. To the resultant solution, hydrochloric acid (0.5 mol/l) was added and the mixture was extracted with dichloromethane. The extract was washed with a saturated aqueous solution of sodium chloride, dried over magnesium sulfate and filtered. After evaporating the solvent, the residue thus obtained was subjected to silica gel column chromatography. Thus, 17.1 g (90%) of the title compound was obtained as an oily substance. The optical purity determined by HPLC was 97% ee.

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