Imidazole → HCID 86708513, compound
Reaction equation
[CH:1]12[O:7][CH:6]1[CH2:5][CH2:4][N:3]([C:8]([O:10][CH2:11][C:12]1[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=1)=[O:9])[CH2:2]2.CN.C(N(CC)CC)C.[C:27](O[C:35]([O:37][C:38]([CH3:41])([CH3:40])[CH3:39])=[O:36])([O:29][C:30]([CH3:33])([CH3:32])[CH3:31])=[O:28].[NH:42]1[CH:46]=[CH:45][N:44]=[CH:43]1.[C:47]([Si:51]([CH3:54])([CH3:53])Cl)([CH3:50])([CH3:49])[CH3:48]>C(O)C.CN(C=O)C.O>[C:38]([O:37][C:35]([N:42]([CH3:46])[C@H:1]1[C@H:6]([O:7][Si:51]([C:47]([CH3:50])([CH3:49])[CH3:48])([CH3:54])[CH3:53])[CH2:5][CH2:4][N:3]([C:8]([O:10][CH2:11][C:12]2[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=2)=[O:9])[CH2:2]1)=[O:36])([CH3:39])([CH3:40])[CH3:41].[C:30]([O:29][C:27]([N:44]([CH3:43])[C@@H:45]1[CH2:46][CH2:4][N:3]([C:8]([O:10][CH2:11][C:12]2[CH:13]=[CH:14][CH:15]=[CH:16][CH:17]=2)=[O:9])[CH2:2][C@H:1]1[O:7][Si:51]([C:47]([CH3:50])([CH3:49])[CH3:48])([CH3:54])[CH3:53])=[O:28])([CH3:33])([CH3:32])[CH3:31]Participants
Reactant 6
Product 2
Reagents, catalysts & solvents 3
Conditions
- Temperature
- 70 °C
Procedure
A mixture of benzyl 7-oxa-3-azabicyclo[4.1.0]heptane-3-carboxylate (0.7 g, 3.00 mmol) and methanamine (3.75 mL, 30.0 mmol) in ethanol (5 mL) was heated in a sealed reaction pressure vessel at 70° C. overnight. The reaction mixture was cooled to room temperature and concentrated to dryness. The residue was dissolved in dichloromethane (5.00 mL), triethylamine (0.502 mL, 3.60 mmol) and di-tert-butyl dicarbonate (0.766 mL, 3.30 mmol) were added and the reaction mixture was stirred at room temperature for 4 h. The reaction mixture was washed with water and brine, dried over magnesium sulfate and concentrated to give a colorless oil. The above oil was dissolved in DMF (5.00 mL), imidazole (0.409 g, 6.00 mmol) and tert-butyldimethylchlorosilane (0.678 g, 4.50 mmol) were added. The mixture was stirred at room temperature overnight. Water was added and the reaction mixture was extracted with ethyl acetate (3×), the organic layer was dried over magnesium sulfate, filtered and concentrated in vacuo, the crude product was purified by flash chromatography on silica gel using an automated ISCO system (80 g gold column, eluting with 5-30% ethyl acetate/hexanes) to give (+/−)-(3R,4R)-benzyl 3-((tert-butoxycarbonyl)(methyl)amino)-4-((tert-butyldimethylsilyl)oxy)piperidine-1-carboxylate (Isomer A, 0.697 g) and (+/−)-(3R,4R)-benzyl 4-((tert-butoxycarbonyl)(methyl)amino)-3-((tert-butyldimethylsilyl)oxy)piperidine-1-carboxylate (Isomer B, 0.556 g). The structures were confirmed by NMR studies (1H-1D, 13C-1D, COSY, NOESY, dept-1H-13C-HSQC, 1H-13C-HMBC).
Workup
- temperatureThe reaction mixture was cooled to room temperature
- concentrationconcentrated to dryness
- dissolutionThe residue was dissolved in dichloromethane (5.00 mL)
- washThe reaction mixture was washed with water and brine
- dry with materialdried over magnesium sulfate
- concentrationconcentrated
- customto give a colorless oil
- stirringThe mixture was stirred at room temperature overnight
- extractionthe reaction mixture was extracted with ethyl acetate (3×)
- dry with materialthe organic layer was dried over magnesium sulfate
- filtrationfiltered
- concentrationconcentrated in vacuo
- customthe crude product was purified by flash chromatography on silica gel using
- washan automated ISCO system (80 g gold column, eluting with 5-30% ethyl acetate/hexanes)
Sources & evidence
- ORD record
- ord-54cbf9e81de24557971af954719855be
- Source dataset
- uspto-grants-2015_01
- Patent number
- US08940736B2
Reaction notes
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