Trifluoroacetic acid → (R)-5-[3-(trifluoromethyl)phenyl]pyrrolidin-2-one
Reaction equation
C(OC([N:8]1[C@@H:12]([C:13]2[CH:18]=[CH:17][CH:16]=[C:15]([C:19]([F:22])([F:21])[F:20])[CH:14]=2)[CH2:11][CH:10](C(O)=O)[C:9]1=[O:26])=O)(C)(C)C.C(O)(C(F)(F)F)=O>C(Cl)Cl>[F:22][C:19]([F:20])([F:21])[C:15]1[CH:14]=[C:13]([C@@H:12]2[NH:8][C:9](=[O:26])[CH2:10][CH2:11]2)[CH:18]=[CH:17][CH:16]=1Participants
4
Procedure
The mixture of (5R)-1-(tert-butoxycarbonyl)-5-[3-(trifluoromethyl)phenyl]-2-oxopyrrolidine-3-carboxylic acid obtained in Step E (ca. 1.21 mmol) and 30% TFA in DCM (6 mL) is stirred at rt for 30 min. The reaction mixture is then dissolved in DCM (120 mL), washed with saturated aq. NaHCO3 (40 mL) and brine (40 mL) and dried over Na2SO4. Concentration to give (R)-5-[3-(trifluoromethyl)phenyl]pyrrolidin-2-one as a slight brown solid (278 mg, 100% overall yield for two steps). This product is used for the next step without further purification. HPLC-MS calculated for C11H10F3NO (M+H+) 230.07, found 230.00.