p-Toluenesulfonic acid → Ethyl 2-(imidazo[1,2-a]pyridin-3-yl)acetate

HRID 910119Notes

Reaction equation

HRID 910119 reaction equation
CO[CH:3](OC)[CH:4]=[CH:5][C:6]([O:8][CH2:9][CH3:10])=[O:7].C1(C)C=CC(S(O)(=O)=O)=CC=1.C(#N)C.[NH2:27][C:28]1[CH:33]=[CH:32][CH:31]=[CH:30][N:29]=1>C(OCC)(=O)C.O>[N:27]1[CH:3]=[C:4]([CH2:5][C:6]([O:8][CH2:9][CH3:10])=[O:7])[N:29]2[CH:30]=[CH:31][CH:32]=[CH:33][C:28]=12

Participants

7

Reactant 4

HCID 6101p-Toluenesulfonic acidHCID 6342AcetonitrileHCID 104392-AminopyridineHCID 68762381HCID 68762381, compound

Product 1

HCID 11171725Ethyl 2-(imidazo[1,2-a]pyridin-3-yl)acetate

Reagents, catalysts & solvents 2

HCID 962WaterSolventHCID 8857Ethyl AcetateSolvent

Procedure

Add ethyl 4,4-dimethoxybut-2-enoate (2.0 g, 11.48 mmol) and p-toluenesulfonic acid (catalytic) to 4:1 acetonitrile:water. Reflux for 1 hour and add 2-aminopyridine (1.08 g, 11.48 mmol). Reflux for 1 hour, dilute with ethyl acetate, and wash saturated aqueous sodium bicarbonate followed by saturated aqueous sodium chloride. Concentrate under reduced pressure to provide the desired compound as a brown oil.

Workup

  1. temperatureReflux for 1 hour
  2. temperatureReflux for 1 hour
  3. washwash saturated aqueous sodium bicarbonate
  4. concentrationConcentrate under reduced pressure

Sources & evidence

ORD record
ord-7dc9ee2fcf4a480ea486155737853933
Source dataset
uspto-grants-2011_09
Patent number
US08022065B2

Reaction notes

Loading…