Water → tert-Butyl 4-ethyl-3-oxopiperazine-1-carboxylate
Reaction equation
[O:1]=[C:2]1[NH:7][CH2:6][CH2:5][N:4]([C:8]([O:10][C:11]([CH3:14])([CH3:13])[CH3:12])=[O:9])[CH2:3]1.[H-].[Na+].I[CH2:18][CH3:19].O>CN(C=O)C.C(OCC)C.C(OCC)(=O)C>[CH2:18]([N:7]1[CH2:6][CH2:5][N:4]([C:8]([O:10][C:11]([CH3:14])([CH3:13])[CH3:12])=[O:9])[CH2:3][C:2]1=[O:1])[CH3:19]Participants
8
Reactant 4
Product 1
Reagents, catalysts & solvents 3
Conditions
- Temperature
- 0 °C
Procedure
To a slurry of tert-butyl 3-oxopiperazine-1-carboxylate (10 g, 49.9 mmol) in 250 mL of DMF, NaH (60% in mineral oil) (2.1 g, 52.4 mmol) was added in portions. The mixture was stirred for 15 min after completion of addition, cooled to 0° C. and iodoethane (5.62 mL, 69.92 mmol) slowly added over 3 min. The resultant suspension was stirred at rt for 2 h. Water was slowly added (400 mL) and then 250 mL of 1:1 ethyl acetate:diethyl ether. The layers were separated and then the organic phase was washed with brine, dried over sodium sulfate, filtered and concentrated to afford tert-butyl 4-ethyl-3-oxopiperazine-1-carboxylate as a colorless oil weighing 6.4 g which was used directly in the next step.
Workup
- additionafter completion of addition
- customThe layers were separated
- washthe organic phase was washed with brine
- dry with materialdried over sodium sulfate
- filtrationfiltered
- concentrationconcentrated
Sources & evidence
- ORD record
- ord-ccd8ae32147542f8a6a50b87ea4b52c5
- Source dataset
- uspto-grants-2016_02
- Patent number
- US09266895B2
Reaction notes
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