Piperazine → 1-(3-Bromopyridin-2-yl)piperazine

HRID 220448

Reaction equation

HRID 220448 reaction equation
[Br:1][C:2]1[C:3](Cl)=[N:4][CH:5]=[CH:6][CH:7]=1.[NH:9]1[CH2:14][CH2:13][NH:12][CH2:11][CH2:10]1.Cl.Cl.N1CCNCC1>O>[Br:1][C:2]1[C:3]([N:9]2[CH2:14][CH2:13][NH:12][CH2:11][CH2:10]2)=[N:4][CH:5]=[CH:6][CH:7]=1

Participants

5

Reactant 3

HCID 4837PiperazineHCID 8893Piperazine DihydrochlorideHCID 6933243-Bromo-2-chloropyridine

Product 1

HCID 132985291-(3-Bromopyridin-2-yl)piperazineYield 71%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Conditions

Temperature
190 °C

Procedure

Add 3-bromo-2-chloro-pyridine (10.08 g, 52.4 mmol) to piperazine (45 g) and piperazine dihydrochloride (83.4 g). Heat the mixture to 190° C. with stirring for one hr. Allow the mixture to cool to about 80° C. then pour the material into water and extract 5 times with DCM. Dry the solution (sodium sulfate), filter and concentrate. Purify using silica gel chromatography, eluting with 15:85 methanol (with 2 M ammonia): DCM to give 1-(3-bromo-pyridin-2-yl)-piperazine as a white solid (8.98 g, 71%).

Workup

  1. temperatureAllow the mixture to cool to about 80° C.
  2. extractionextract 5 times with DCM
  3. dry with materialDry the solution (sodium sulfate)
  4. filtrationfilter
  5. concentrationconcentrate
  6. customPurify
  7. washeluting with 15:85 methanol (with 2 M ammonia)

Sources & evidence

ORD record
ord-db0422694fed4110a18c86f5a7031188
Source dataset
uspto-grants-2012_06
Patent number
US08202873B2

Linked notes

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