Diisopropylethylamine → (4-Methyl-3-oxo-piperazin-1-yl)-carbamic acid t-butyl ester
Reaction equation
Cl.[CH3:2][N:3]1[CH2:8][CH2:7][NH:6][CH2:5][C:4]1=[O:9].C(N(CC)C(C)C)(C)C.[CH3:19][C:20]([O:23][C:24]([N:26]1C(C2C=CC(C#N)=CC=2)O1)=[O:25])([CH3:22])[CH3:21]>ClCCl>[C:20]([O:23][C:24](=[O:25])[NH:26][N:6]1[CH2:7][CH2:8][N:3]([CH3:2])[C:4](=[O:9])[CH2:5]1)([CH3:22])([CH3:21])[CH3:19]Participants
Reactant 3
Product 1
Reagents, catalysts & solvents 1
Conditions
- Temperature
- 0 °C
Procedure
Methyl-2-piperazinone hydrochloride (1:1) (300 mg, 1.99 mmol) was combined with dichloromethane (20 mL) to give a light yellow suspension. N,N-Diisopropylethylamine (309 mg, 417 μl, 2.39 mmol) was added at 0° C. Subsequently 3-(4-cyanophenyl)-2-oxaziridinecarboxylic acid 1,1-dimethylethyl ester (441 mg, 1.79 mmol) in dichloromethane (10 mL) was added during 35 min at 0° C. and the reaction mixture was stirred for 1 h at 0° C. Afterwards the reaction mixture was concentrated in vacuo and the residue was purified by flash chromatography (silica gel, 20 g, 0% to 100% ethyl acetate in n-heptane) to deliver an oil contaminated with 4-cyano-benzaldehyde. This material was purified by a second chromatography (aminophase 5 g, ethyl acetate/n-heptane 1/1) to give the title compound (67 mg, 15%) as white solid; GC-MS (EI) 229.0 (M)+.
Workup
- customto give a light yellow suspension
- concentrationAfterwards the reaction mixture was concentrated in vacuo
- customthe residue was purified by flash chromatography (silica gel, 20 g, 0% to 100% ethyl acetate in n-heptane)
- customThis material was purified by a second chromatography (aminophase 5 g, ethyl acetate/n-heptane 1/1)
Sources & evidence
- ORD record
- ord-6c67295c878047318f72056e79ad9088
- Source dataset
- uspto-grants-2014_02
- Patent number
- US08648099B2
Reaction notes
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