Reaktion #8544

Reaktionsgleichung

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

phosphate

hydrochloric acid

→

title compound

(2S)-2-(2,3,4-trifluoroanilino)propionic acid

Lösungsmittel

methylene chloride

Reaktionsbedingungen

Aufarbeitung

1. 1
   workup.ADDITIONAfter adding Protease N (
2. 2
   workup.STIRRINGThe mixture was further stirred for 14 hours
3. 3
   Sonstigethe liquid reaction mixture
4. 4
   Filtrationwas filtered through celite
5. 5
   Sonstigeseparated
6. 6
   WaschenThe organic layer was washed with a 5% aqueous solution of sodium hydrogencarbonate
7. 7
   Trocknena saturated aqueous solution of sodium chloride and then dried over anhydrous magnesium sulfate
8. 8
   SonstigeNext, the solvent was evaporated under reduced pressure to thereby give methyl (2R)-2-(2,3,4-trifluoroanilino)propionate (0.94 g)
9. 9
   SonstigeOn the other hand, the all aqueous layers obtained by the separation
10. 10
    Extraktionfollowed by extraction with IPE
11. 11
    TrocknenThe organic layer was dried over anhydrous magnesium sulfate
12. 12
    Sonstigeevaporated

Vorschrift

Methyl 2-(2,3,4-trifluoroanilino)propionate (2.0 g) was suspended in a 0.1 M phosphate buffer solution (pH 6.5; 400 ml). After adding Protease N (manufactured by Amano Seiyaku, originating in a bacterium belonging to the genus Bacillus; 0.4 g), the mixture was gently stirred. The mixture was further stirred for 14 hours while maintaining at 30° C. After adding methylene chloride, the liquid reaction mixture was filtered through celite to eliminate denatured protein and then separated. The organic layer was washed with a 5% aqueous solution of sodium hydrogencarbonate and a saturated aqueous solution of sodium chloride and then dried over anhydrous magnesium sulfate. Next, the solvent was evaporated under reduced pressure to thereby give methyl (2R)-2-(2,3,4-trifluoroanilino)propionate (0.94 g). The optical purity of this product was 98% ee. On the other hand, the all aqueous layers obtained by the separation were combined and adjusted to pH 2 with 10% hydrochloric acid followed by extraction with IPE. The organic layer was dried over anhydrous magnesium sulfate and evaporated. Thus, the title compound was obtained as a crude product (0.96 g). The optical purity of this product was 96% ee. Further, the crude product was recrystallized from a solvent mixture of isopropyl ether with hexane. Thus, the title compound of 100% ee was obtained. The 1H-NMR and IR spectral data of this product was identical with those of the compound obtained in Example 28.

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