Ethyl bromoacetate → 1-ethoxycarbonylmethyl-2,3-dihydro-1H-imidazo[1,2-b]pyrazole

HRID 1681654Notes

Reaction equation

HRID 1681654 reaction equation
[NH:1]1[C:8]2[N:4]([N:5]=[CH:6][CH:7]=2)[CH2:3][CH2:2]1.Br[CH2:10][C:11]([O:13][CH2:14][CH3:15])=[O:12].C(=O)(O)[O-].[K+].C(OCC)(=O)C>CS(C)=O.O>[CH2:14]([O:13][C:11]([CH2:10][N:1]1[C:8]2[N:4]([N:5]=[CH:6][CH:7]=2)[CH2:3][CH2:2]1)=[O:12])[CH3:15]

Participants

7

Reactant 4

HCID 7748Ethyl bromoacetateHCID 8857Ethyl AcetateHCID 2424712,3-Dihydro-1H-imidazo(1,2-b)pyrazoleHCID 516893Potassium Bicarbonate

Product 1

HCID 189552941-ethoxycarbonylmethyl-2,3-dihydro-1H-imidazo[1,2-b]pyrazole

Reagents, catalysts & solvents 2

HCID 679Dimethyl SulfoxideSolventHCID 962WaterSolvent

Procedure

To a solution of 2,3-dihydro-1H-imidazo[1,2-b]pyrazole (19 g) in dimethylsulfoxide (95 ml) were added ethyl bromoacetate (20.4 ml) and potassium bicarbonate (30 g) under ice-cooling. The mixture was stirred at room temperature for 4 hours. The reaction mixture was poured into a mixture of ethyl acetate (1.5 l) and water (500 ml). The separated organic layer was washed with water and brine, and dried over magnesium sulfate. The solvent was evaporated and the residue was subjected to column chromatography on silica gel using ethyl acetate as an eluent. Fractions containing the object compound were combined and evaporated in vacuo to give 1-ethoxycarbonylmethyl-2,3-dihydro-1H-imidazo[1,2-b]pyrazole (20.3 g).

Workup

  1. temperaturecooling
  2. washThe separated organic layer was washed with water and brine
  3. dry with materialdried over magnesium sulfate
  4. customThe solvent was evaporated
  5. additionFractions containing the object compound
  6. customevaporated in vacuo

Sources & evidence

ORD record
ord-e6a57bdc4e0240a6a429c26a30bb6a5c
Source dataset
uspto-grants-1992_12
Patent number
US05173485

Reaction notes

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