Trifluoroacetic acid → HCID 58551585, compound

Reaction equation

FC(F)(F)C(O)=O.[OH:8][C:9]1[CH:10]=[C:11]([CH:16]=[CH:17][C:18]=1[N:19]1[CH:23]=[CH:22][CH:21]=[CH:20]1)[C:12]([O:14][CH3:15])=[O:13].O=[C:25]1[CH2:30][CH2:29][N:28]([C:31]([O:33][C:34]([CH3:37])([CH3:36])[CH3:35])=[O:32])[CH2:27][CH2:26]1>ClCCl>[N:28]1([C:31]([O:33][C:34]([CH3:37])([CH3:36])[CH3:35])=[O:32])[CH2:29][CH2:30][C:25]2([O:8][C:9]3[CH:10]=[C:11]([C:12]([O:14][CH3:15])=[O:13])[CH:16]=[CH:17][C:18]=3[N:19]3[CH:23]=[CH:22][CH:21]=[C:20]23)[CH2:26][CH2:27]1

Participants

Procedure

Trifluoroacetic acid (3.15 g, 2.13 mL, 27.6 mmol) was added dropwise to a solution of methyl 3-hydroxy-4-pyrrol-1-yl-benzoate (3.00 g, 13.8 mmol) and tert-butyl 4-oxopiperidine-1-carboxylate (3.00 g, 15.2 mmol) in dichloromethane (60 mL) and the reaction mixture was stirred at room temperature for 6 hours. The reaction mixture was washed with water and 1N NaOH. The organics were dried over sodium sulfate, filtered and evaporated. The residue was purified by silica gel chromatography eluting with 0-30% EtOAc in Hexanes. The pure fractions were combined and concentrated to give 1′-tert-butyl 7-methyl spiro[benzo[b]pyrrolo[1,2-d][1,4]oxazine-4,4′-piperidine]-1′,7-dicarboxylate. ESI-MS m/z calc. 398.4. found 399.5 (M+1)+. Retention time: 2.13 minutes (3 min run).