Bromobenzene → Piperazine, 1-methyl-4-phenyl-

HRID 912399Notes

Reaction equation

HRID 912399 reaction equation
Br[C:2]1[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=1.[CH3:8][N:9]1[CH2:14][CH2:13][NH:12][CH2:11][CH2:10]1.CC(C)([O-])C.[K+]>>[CH3:8][N:9]1[CH2:14][CH2:13][N:12]([C:2]2[CH:7]=[CH:6][CH:5]=[CH:4][CH:3]=2)[CH2:11][CH2:10]1

Participants

4

Reactant 3

HCID 7961BromobenzeneHCID 531671-MethylpiperazineHCID 23665647Potassium tert-butoxide

Product 1

HCID 200991Piperazine, 1-methyl-4-phenyl-Yield 74.4%

Procedure

A 1 L flask was charged with 141.3 g of bromobenzene, 30.1 g of 1-methylpiperazine and 43.8 g of potassium tert-butoxide. The flask was then placed on an ice bath for 10 minutes and the contents rapidly stirred. 2.04 g of “PEPPSI” catalyst[1,3-bis(2,6-diisopropylphenyl)imidazol-2-ylidene](3-chloropyridyl)-palladium (II) dichloride was then added and the flask fitted with a reflux condenser. The reaction was refluxed under a nitrogen atmosphere for 2 hours and then cooled to room temperature. The reaction mixture was then filtered through a pad of 800 mL of silica gel in a 2 L D-filter flask and the pad subsequently rinsed with 600 mL of ether. Then the product was extracted from the pad with ethanol. Evaporation of the ethanol gave 39.4 g of 1-methyl-4-phenylpiperazine.

Workup

  1. customthe flask fitted with a reflux condenser
  2. temperatureThe reaction was refluxed under a nitrogen atmosphere for 2 hours
  3. filtrationThe reaction mixture was then filtered through a pad of 800 mL of silica gel in a 2 L D-filter flask
  4. washthe pad subsequently rinsed with 600 mL of ether
  5. extractionThen the product was extracted from the pad with ethanol
  6. customEvaporation of the ethanol

Sources & evidence

ORD record
ord-b3f6546dccf24fc48cf06ac33f43e005
Source dataset
uspto-grants-2011_09
Patent number
US08025863B2

Reaction notes

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