Ethyl 2-chloroacetoacetate → Ethyl 7-methoxy-2-methylimidazo[1,2-a]pyridine-3-carboxylate

HRID 273320Notes

Reaction equation

HRID 273320 reaction equation
[CH3:1][O:2][C:3]1[CH:8]=[CH:7][N:6]=[C:5]([NH2:9])[CH:4]=1.Cl[CH:11]([C:17]([CH3:19])=O)[C:12]([O:14][CH2:15][CH3:16])=[O:13]>CCO>[CH3:1][O:2][C:3]1[CH:8]=[CH:7][N:6]2[C:11]([C:12]([O:14][CH2:15][CH3:16])=[O:13])=[C:17]([CH3:19])[N:9]=[C:5]2[CH:4]=1

Participants

4

Reactant 2

HCID 11858Ethyl 2-chloroacetoacetateHCID 108987152-Amino-4-Methoxypyridine

Product 1

HCID 53485249Ethyl 7-methoxy-2-methylimidazo[1,2-a]pyridine-3-carboxylateYield 134.5%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Procedure

A mixture of 4-methoxy-2-aminopyridine (1.07 g, 8.6 mmol) and ethyl 2-chloroacetoacetate (5.4 g) in EtOH (50 mL) was refluxed for 24 h. The reaction mixture was then concentrated to half its volume, extracted with CH2Cl2, washed with brine and then water, and dried over anhydrous MgSO4. The solvent was removed in vacuo and the residue was purified on a silica gel column eluting with EtOAc and then MeOH/CH2Cl2 (1:9) to give ethyl 7-methoxy-2-methylimidazo[1,2-a]pyridine-3-carboxylate (2.71 g, 90%).

Workup

  1. temperaturewas refluxed for 24 h
  2. concentrationThe reaction mixture was then concentrated to half its volume
  3. extractionextracted with CH2Cl2
  4. washwashed with brine
  5. dry with materialwater, and dried over anhydrous MgSO4
  6. customThe solvent was removed in vacuo
  7. customthe residue was purified on a silica gel column
  8. washeluting with EtOAc

Sources & evidence

ORD record
ord-62687a8a8646469496bd4024e61d652a
Source dataset
uspto-grants-2008_11
Patent number
US07456289B2

Reaction notes

Loading…