Trifluoroacetic acid → (2R,4R)-4-amino-2-methyl-pentanoic acid ethyl ester trifluoroacetate
Reaction equation
[CH2:1]([O:3][C:4](=[O:18])[C@H:5]([CH3:17])[CH2:6][C@H:7]([NH:9]C(OC(C)(C)C)=O)[CH3:8])[CH3:2].[F:19][C:20]([F:25])([F:24])[C:21]([OH:23])=[O:22]>>[F:19][C:20]([F:25])([F:24])[C:21]([OH:23])=[O:22].[CH2:1]([O:3][C:4](=[O:18])[C@H:5]([CH3:17])[CH2:6][C@H:7]([NH2:9])[CH3:8])[CH3:2]Participants
3
Procedure
Next, (2R,4R)-4-tert-butoxycarbonylamino-2-methyl-pentanoic acid ethyl ester (142 mg, 0.548 mmol) is added to trifluoroacetic acid (5 mL). After 10 minutes, the solvent is removed under reduced pressure. Methylene chloride is added and the solvent is removed under reduced pressure to give (2R,4R)-4-amino-2-methyl-pentanoic acid ethyl ester trifluoroacetate. This material is used directly in the subsequent coupling reaction.
Workup
- customthe solvent is removed under reduced pressure
- addition