1-Bromo-3-chlorobenzene → (R)-Tert-butyl 3-(3-chlorobenzoyl)piperidine-1-carboxylate
Reaction equation
Br[C:2]1[CH:7]=[CH:6][CH:5]=[C:4]([Cl:8])[CH:3]=1.[Li]CCCC.CON(C)[C:17]([C@@H:19]1[CH2:24][CH2:23][CH2:22][N:21]([C:25]([O:27][C:28]([CH3:31])([CH3:30])[CH3:29])=[O:26])[CH2:20]1)=[O:18]>C1COCC1>[Cl:8][C:4]1[CH:3]=[C:2]([CH:7]=[CH:6][CH:5]=1)[C:17]([C@@H:19]1[CH2:24][CH2:23][CH2:22][N:21]([C:25]([O:27][C:28]([CH3:31])([CH3:30])[CH3:29])=[O:26])[CH2:20]1)=[O:18]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- -78 °C
Procedure
To a solution of 1-bromo-3-chlorobenzene (15 g, 78.3 mmol) in anhydrous THF (150 mL) cooled to −78° C. was added dropwise a solution of 2.5 M n-BuLi in hexanes (31.3 mL, 78.34 mmol). The reaction mixture was stirred at −78° C. for 1 h and a solution of (R)-tert-butyl 3-(methoxy(methyl)carbamoyl)piperidine-1-carboxylate (17.8 g, 65.3 mmol) in anhydrous THF (50 mL) was added dropwise. After addition, the mixture was allowed to warm to rt and stirred for 2 h. The mixture was quenched with satd aq NH4Cl (250 mL) and extracted with EtOAc (3×150 mL). The combined organic layers were washed with brine, dried over Na2SO4 and concentrated in vacuo. The residue was purified by flash column chromatography (petroleum ether/EtOAc 5:95) to give (R)-tert-butyl 3-(3-chlorobenzoyl)piperidine-1-carboxylate (12.9 g, 51%). 1H NMR (400 MHz, CDCl3): 1.45 (s, 9H), 1.54-1.73 (m, 2H), 1.75 (m, 1H), 2.00 (m, 1H), 2.71-2.78 (m, 1H), 2.93 (m, 2H), 3.30-3.35 (m, 1H), 4.22 (m, 1H), 7.39-7.42 (t, 1H), 7.52 (d, 1H), 7.89 (d, 1H), 7.90 (m, 1H). MS m/z 324 (M+H+).
Workup
- additionAfter addition
- temperatureto warm to rt
- stirringstirred for 2 h
- customThe mixture was quenched with satd aq NH4Cl (250 mL)
- extractionextracted with EtOAc (3×150 mL)
- washThe combined organic layers were washed with brine
- dry with materialdried over Na2SO4
- concentrationconcentrated in vacuo
- customThe residue was purified by flash column chromatography (petroleum ether/EtOAc 5:95)
Sources & evidence
- ORD record
- ord-ca582425d9f64a27bb138769ee1df57b
- Source dataset
- uspto-grants-2013_07
- Patent number
- US08487108B2
Reaction notes
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