Propargyl bromide → 1-Methyl-4-(prop-2-yn-1-yl)piperazine

HRID 276822Notes

Reaction equation

HRID 276822 reaction equation
[CH2:1](Br)[C:2]#[CH:3].[CH3:5][N:6]1[CH2:11][CH2:10][NH:9][CH2:8][CH2:7]1.C(=O)([O-])[O-].[Cs+].[Cs+]>CC(C)=O>[CH3:5][N:6]1[CH2:11][CH2:10][N:9]([CH2:1][C:2]#[CH:3])[CH2:8][CH2:7]1

Participants

5

Reactant 3

HCID 7842Propargyl bromideHCID 10796Cesium carbonateHCID 531671-Methylpiperazine

Product 1

HCID 135140911-Methyl-4-(prop-2-yn-1-yl)piperazineYield 27.1%

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

Propargyl bromide (23.8 g, 200 mmol) was added dropwise to a mixture of 1-methyl-piperazine (20 g, 200 mmol) and cesium carbonate (65 g, 200 mmol) in 350 mL of acetone. The mixture was stirred overnight under nitrogen at room temperature. The inorganic salts were then filtered off, and the solvent was removed. The residue was dissolved in saturated sodium bicarbonate solution and extracted with ethyl acetate. The organic extracts were then evaporated to give 7.5 g of 1-methyl-4-prop-2-ynyl-piperazine: mass spectrum (m/e): M+H 139.

Workup

  1. filtrationThe inorganic salts were then filtered off
  2. customthe solvent was removed
  3. dissolutionThe residue was dissolved in saturated sodium bicarbonate solution
  4. extractionextracted with ethyl acetate
  5. customThe organic extracts were then evaporated

Sources & evidence

ORD record
ord-34ac721c40d44dd198bfb654e63ce394
Source dataset
uspto-grants-2002_03
Patent number
US06355636B1

Reaction notes

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