Sodium borohydride → Tert-butyl 5-chlorospiro[indoline-3,4'-piperidine]-1'-carboxylate
Reaction equation
[BH4-].[Na+].[Cl:3][C:4]1[CH:5]=[C:6]2[C:12]3([CH2:17][CH2:16][N:15]([C:18]([O:20][C:21]([CH3:24])([CH3:23])[CH3:22])=[O:19])[CH2:14][CH2:13]3)[CH:11]=[N:10][C:7]2=[CH:8][CH:9]=1>CCO>[Cl:3][C:4]1[CH:5]=[C:6]2[C:12]3([CH2:13][CH2:14][N:15]([C:18]([O:20][C:21]([CH3:24])([CH3:23])[CH3:22])=[O:19])[CH2:16][CH2:17]3)[CH2:11][NH:10][C:7]2=[CH:8][CH:9]=1Participants
4
Procedure
NaBH4 (1.29 g, 34.0 mmol) was added to a stirred solution of tert-butyl 5-chlorospiro[indole-3,4′-piperidine]-1′-carboxylate (2.57 g, 8.01 mmol) in absolute EtOH (100 mL) portionwise. The reaction was stirred at about room temperature overnight. The reaction was concentrated. The crude residue was taken up in DCM, washed with water and brine, dried over MgSO4, filtered, and concentrated. The crude residue was purified by column chromatography (25-35% EtOAc/Hexane) to yield tert-butyl 5-chlorospiro[indoline-3,4′-piperidine]-1′-carboxylate. LCMS (APCI+) m/z 223, 225 [M+H-Boc]+; Rt=3.86 min.