Hydrochloric Acid → Methyl (2S)-2-(2,3,4-trifluoroanilino)propionate

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 thereinto. 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.

1. temperatureUnder ice-cooling
2. temperatureThen it was cooled to 0° C. again
3. stirringThe mixture was stirred at the same temperature for 17 hours
4. extractionthe mixture was extracted with dichloromethane
5. washThe extract was washed with a saturated aqueous solution of sodium chloride
6. dry with materialdried over magnesium sulfate
7. filtrationfiltered
8. customAfter evaporating the solvent
9. customthe residue thus obtained

ORD record

ord-5234169ef35346aaae211ebdd1ddbd8a

Source dataset

uspto-grants-2007_03

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07189847B2