F[C:2]1[CH:7]=[CH:6][C:5]([N+:8]([O-:10])=[O:9])=[C:4]([O:11][CH3:12])[CH:3]=1.[NH:13]1[CH2:18][CH2:17][CH2:16][C@H:15]([C:19]([OH:21])=[O:20])[CH2:14]1.C([O-])([O-])=O.[K+].[K+]>CN(C=O)C>[CH3:12][O:11][C:4]1[CH:3]=[C:2]([N:13]2[CH2:18][CH2:17][CH2:16][C@H:15]([C:19]([OH:21])=[O:20])[CH2:14]2)[CH:7]=[CH:6][C:5]=1[N+:8]([O-:10])=[O:9](S)-1-(3-Methoxy-4-nitro-phenyl)-piperidine-3-carboxylic acid was prepared by reacting 4-fluoro-2-methoxy-1-nitro-benzene (342 mg, 2.0 mmol) with (S)-Piperidine-3-carboxylic acid (258 mg, 2.0 mmol) at 80° C. in DMF using K2CO3 (608 mg, 2.20 mmol) as a base scavenger. After 16 h the reaction was concentrated under reduced pressure and the residue was partitioned between EtOAc and water. The aqueous phase was acidified with 1N HCl to pH 4-5. The resulting yellow solid was filtered, rinsed with water, and air dried overnight to yield 352 mg (63%) of (S)-1-(3-Methoxy-4-nitro-phenyl)-piperidine-3-carboxylic acid as a yellow solid. LC/MS (E/I+) 281.08 (M+H).
Wird geladen…
