Piperazine → 1-(4-Nitrophenyl)piperazine

HRID 2278832Notes

Reaction equation

HRID 2278832 reaction equation
[N+:1]([C:4]1[CH:9]=[CH:8][C:7](Br)=[CH:6][CH:5]=1)([O-:3])=[O:2].[NH:11]1[CH2:16][CH2:15][NH:14][CH2:13][CH2:12]1.[O-]P([O-])([O-])=O.[K+].[K+].[K+]>[Cu]I.C(O)(C)C>[N+:1]([C:4]1[CH:9]=[CH:8][C:7]([N:11]2[CH2:16][CH2:15][NH:14][CH2:13][CH2:12]2)=[CH:6][CH:5]=1)([O-:3])=[O:2]

Participants

6

Reactant 3

HCID 4837PiperazineHCID 114661-Bromo-4-nitrobenzeneHCID 62657Potassium Phosphate, Tribasic

Product 1

HCID 804471-(4-Nitrophenyl)piperazineYield 49.4%

Reagents, catalysts & solvents 2

HCID 24350Copper(1+) iodide; Copper(I) iodide; Cuprous iodide; Cuprous iodide (CuI)Catalyst2×HCID 3776IsopropanolSolvent

Procedure

8.10 g p-nitro-bromobenzene was added into a 250 ml round-bottom flask containing 50 mL isopropanol, then 7.00 g anhydrous piperazine, 15.00 g anhydrous K3PO4 and 4 ml glycol was added, then 2.00 g CuI was added as catalyster under nitrogen atmosphere (the small-scale reaction was carried out in the absence of nitrogen atmosphere, the results showed mat the yield was low probably because of the oxidation of CuI). The reaction mixture was refluxed for two days under nitrogen atmosphere. The crude product was filtered and concentrated. The concentrate was extracted with chloroform/water. The chloroform extract was dried by anhydrous Na2SO4. Based on higher polarity of product and lower polarity of the starting material, the extract was purified by column-chromatography with gradient elution of petroleum ether:ethyl acetate:ethanol in differ ratio, concentrated the eluate, to produce N-4-nitro-phenyl piperazine as yellow solid (4.10 g, 49.4% yield). Mp: 126-128° C. (lit.: 130-132° C.)

Workup

  1. customthe small-scale reaction
  2. temperatureThe reaction mixture was refluxed for two days under nitrogen atmosphere
  3. filtrationThe crude product was filtered
  4. concentrationconcentrated
  5. extractionThe concentrate was extracted with chloroform/water
  6. extractionThe chloroform extract
  7. dry with materialwas dried by anhydrous Na2SO4
  8. customthe extract was purified by column-chromatography with gradient elution of petroleum ether
  9. concentrationethyl acetate:ethanol in differ ratio, concentrated the eluate,

Sources & evidence

ORD record
ord-075793d646804c5296524f22ebb697b6
Source dataset
uspto-grants-2015_09
Patent number
US09133195B2

Reaction notes

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