Dimethylcarbamoyl Chloride → tert-Butyl 4-(dimethylcarbamoyl)piperazine-1-carboxylate
Reaction equation
[CH3:1][C:2]([CH3:13])([O:4][C:5]([N:7]1[CH2:12][CH2:11][NH:10][CH2:9][CH2:8]1)=[O:6])[CH3:3].C(N(CC)CC)C.[CH3:21][N:22]([CH3:26])[C:23](Cl)=[O:24].C(=O)([O-])O.[Na+]>ClCCl>[CH3:3][C:2]([CH3:13])([O:4][C:5]([N:7]1[CH2:8][CH2:9][N:10]([C:23]([N:22]([CH3:26])[CH3:21])=[O:24])[CH2:11][CH2:12]1)=[O:6])[CH3:1]Participants
Procedure
To a solution of 1.92 g 1-(1,1-dimethylethyloxycarbonyl)piperazine in 11 mL of dichlorometbane and 1.5 mL of triethylamine at room temperature was added dropwise 1 mL of dimethylcarbamylchloride. After 16 hours 5% aqueous sodium hydrogencarbonate and dichloromethane were added, the organic layer separated, dried over magnesium sulfate and concentrated. Column chromatography on silica gel (dichloromethane/methanol=95/5 v/v) yielded 1.34 g 1-(1,1-dimethylethyloxycarbonyl)-4-(dimethylaminocarbonyl)piperazine. This compound was dissolved in a 3N hydrogen chloride solution in methanol at 0° C. After 15 min the reaction mixture was allowed to warm to room temperature and After stirring for 3 days at room temperature the reaction mixture was concentrated to give 1.06 g of 1-(dimethylaminocarbonyl)piperazine hydrochloride. rf=0.29, SiO2: dichloromethane/methanol=4/I v/v.
Workup
- customthe organic layer separated
- dry with materialdried over magnesium sulfate
- concentrationconcentrated
Sources & evidence
- ORD record
- ord-899c61f67f044912b4adeb5a6479451f
- Source dataset
- uspto-grants-2001_02
- Patent number
- US06194409B1
Reaction notes
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