Potassium Carbonate → tert-Butyl 4-(2-cyano-4-nitrophenyl)piperazine-1-carboxylate
Reaction equation
F[C:2]1[CH:9]=[CH:8][C:7]([N+:10]([O-:12])=[O:11])=[CH:6][C:3]=1[C:4]#[N:5].C(=O)([O-])[O-].[K+].[K+].[C:19]([O:23][C:24]([N:26]1[CH2:31][CH2:30][NH:29][CH2:28][CH2:27]1)=[O:25])([CH3:22])([CH3:21])[CH3:20]>C(O)C>[C:19]([O:23][C:24]([N:26]1[CH2:31][CH2:30][N:29]([C:2]2[CH:9]=[CH:8][C:7]([N+:10]([O-:12])=[O:11])=[CH:6][C:3]=2[C:4]#[N:5])[CH2:28][CH2:27]1)=[O:25])([CH3:22])([CH3:20])[CH3:21]Participants
5
Conditions
- Temperature
- 80 °C
Procedure
A solution of 2-fluoro-5-nitrobenzonitrile (500 mg, 3.0 mmol) in ethanol (35 mL) was treated with potassium carbonate (420 mg, 3.0 mmol) and piperazine-1-carboxylic acid tert-butyl ester (560 mg, 3.0 mmol). The reaction mixture was stirred at 80° C. for 1 h, then cooled and partitioned between ethyl acetate and water. The organic layer was then collected, dried over sodium sulfate, filtered and evaporated to a yellow residue. Purification using flash chromatography yielded 4-(2-cyano-4-nitro-phenyl)-piperazine-1-carboxylic acid tert-butyl ester (590 mg, 59% yield) as a bright yellow solid. HRMS calcd for C16H20N4O4 (M+Na) 355.1377, obsd 355.1376.
Workup
- temperaturecooled
- custompartitioned between ethyl acetate and water
- customThe organic layer was then collected
- dry with materialdried over sodium sulfate
- filtrationfiltered
- customevaporated to a yellow residue
- customPurification
Sources & evidence
- ORD record
- ord-f29d7ee986b546ebbdaea6eaf65c1150
- Source dataset
- uspto-grants-2012_02
- Patent number
- US08115011B2
Reaction notes
Loading…