3,3-Dimethylbutanal → 4-(3,3-Dimethyl-butyl)-piperazine-1-carboxylic Acid tert-butyl Ester
Reaction equation
[C:1]([N:8]1[CH2:13][CH2:12][NH:11][CH2:10][CH2:9]1)([O:3][C:4]([CH3:7])([CH3:6])[CH3:5])=[O:2].[CH3:14][C:15]([CH3:20])([CH3:19])[CH2:16][CH:17]=O.C([BH3-])#N.[Na+]>CO.C(O)(=O)C>[C:4]([O:3][C:1]([N:8]1[CH2:9][CH2:10][N:11]([CH2:17][CH2:16][C:15]([CH3:20])([CH3:19])[CH3:14])[CH2:12][CH2:13]1)=[O:2])([CH3:7])([CH3:6])[CH3:5]Participants
5
Procedure
To a solution of 1-boc-piperazine (8.19 g, 43.9 mmol) in methanol/acetic acid (99:1, v/v, 100 ml) was added 3,3-dimethylbutyraldehyde (4.0 g, 40.0 mmol) and the resulting mixture was stirred at room temperature for 1 h. Sodium cyanoborohydride (3.27 g, 51.9 mmol) was added, and the resulting mixture was stirred at room temperature for 18 h then concentrated in vacuo. The residue was dissolved in EtOAc and the resulting solution was washed with saturated NaHCO3, water and brine, dried and concentrated in vacuo. The residue was purified by flash chromatography on silica gel (eluant; 5% methanol:95% EtOAc) to yield the title compound (9.1 g, 84%).
Workup
- stirringthe resulting mixture was stirred at room temperature for 18 h
- concentrationthen concentrated in vacuo
- dissolutionThe residue was dissolved in EtOAc
- washthe resulting solution was washed with saturated NaHCO3, water and brine
- customdried
- concentrationconcentrated in vacuo
- customThe residue was purified by flash chromatography on silica gel (eluant; 5% methanol:95% EtOAc)
Sources & evidence
- ORD record
- ord-3acfc75b9f88465ca03f33de078bae6d
- Source dataset
- uspto-grants-2012_06
- Patent number
- US08202858B2
Reaction notes
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