Piperazine → 6-Piperazin-1-ylimidazo[1,2-b]pyridazine-2-carboxylic acid ethyl ester

HRID 1985632Notes

Reaction equation

HRID 1985632 reaction equation
[CH2:1]([O:3][C:4]([C:6]1[N:7]=[C:8]2[CH:13]=[CH:12][C:11](Cl)=[N:10][N:9]2[CH:15]=1)=[O:5])[CH3:2].[NH:16]1[CH2:21][CH2:20][NH:19][CH2:18][CH2:17]1.C(=O)([O-])[O-].[K+].[K+]>C1(C)C=CC=CC=1>[CH2:1]([O:3][C:4]([C:6]1[N:7]=[C:8]2[CH:13]=[CH:12][C:11]([N:16]3[CH2:21][CH2:20][NH:19][CH2:18][CH2:17]3)=[N:10][N:9]2[CH:15]=1)=[O:5])[CH3:2]

Participants

5

Reactant 3

HCID 4837PiperazineHCID 11430Potassium CarbonateHCID 2779714ethyl 6-chloroimidazo[1,2-b]pyridazine-2-carboxylate

Product 1

HCID 668640036-Piperazin-1-ylimidazo[1,2-b]pyridazine-2-carboxylic acid ethyl ester

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

A mixture of 6-chloroimidazo[1,2-b]pyridazine-2-carboxylic acid ethyl ester (1.000 g, 4.432 mmol), piperizine (0.458 g, 5.318 mmol) and potassium carbonate (0.620 g, 4.485 mmol) in 50 mL of toluene was refluxed for 48 hours. The reaction mixture was concentrated in vacuo, diluted with water and extracted with ethyl acetate. The crude product, 6-piperazin-1-ylimidazo[1,2-b]pyridazine-2-carboxylic acid ethyl ester, obtained upon removal of solvent was used for next step reaction without further purification. Yield 1.016 g, 83%.

Workup

  1. temperaturewas refluxed for 48 hours
  2. concentrationThe reaction mixture was concentrated in vacuo
  3. additiondiluted with water
  4. extractionextracted with ethyl acetate

Sources & evidence

ORD record
ord-7ee9207ad11b40b78e127985c5b2941d
Source dataset
uspto-grants-2009_06
Patent number
US07547698B2

Reaction notes

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