Potassium Carbonate → tert-Butyl 4-(2-cyano-4-nitrophenyl)piperazine-1-carboxylate

HRID 557710Notes

Reaction equation

HRID 557710 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

Reactant 3

HCID 11430Potassium CarbonateHCID 143452tert-Butyl piperazine-1-carboxylateHCID 5194172-Fluoro-5-nitrobenzonitrile

Product 1

HCID 22227995tert-Butyl 4-(2-cyano-4-nitrophenyl)piperazine-1-carboxylateYield 59.2%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

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

  1. temperaturecooled
  2. custompartitioned between ethyl acetate and water
  3. customThe organic layer was then collected
  4. dry with materialdried over sodium sulfate
  5. filtrationfiltered
  6. customevaporated to a yellow residue
  7. customPurification

Sources & evidence

ORD record
ord-71c2aaa4cc3a4854957e87ed703648d6
Source dataset
uspto-grants-2011_11
Patent number
US08058299B2

Reaction notes

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