تفاعل #8524

معادلة التفاعل

2,3,4-trifluoroaniline

methyl D-lactate

2,6-lutidine

hydrochloric acid

trifluoromethanesulfonic acid

→

title compound

المردود 90.0%

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

المردود 90.0%

المذيبات

dichloromethane

dichloromethane

ظروف التفاعل

المعالجة

1. 1
   درجة الحرارةUnder ice-cooling
2. 2
   درجة الحرارةThen it was cooled to 0° C. again
3. 3
   workup.STIRRINGThe mixture was stirred at the same temperature for 17 hours
4. 4
   استخلاصthe mixture was extracted with dichloromethane
5. 5
   غسيلThe extract was washed with a saturated aqueous solution of sodium chloride
6. 6
   تجفيفdried over magnesium sulfate
7. 7
   ترشيحfiltered
8. 8
   أخرىAfter evaporating the solvent
9. 9
   أخرىthe residue thus obtained

الإجراء التجريبي

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.

المصدر