Pyridine → 2-Methylimidazo[1,2-a]pyridine-3-carbonitrile

HRID 2282209Notes

Reaction equation

HRID 2282209 reaction equation
[CH3:1][C:2]1[N:3]=[C:4]2[CH:9]=[CH:8][CH:7]=[CH:6][N:5]2[C:10]=1[C:11]([NH2:13])=O.N1C=CC=CC=1.FC(F)(F)C(OC(=O)C(F)(F)F)=O.C(=O)(O)[O-].[Na+]>O1CCCC1>[CH3:1][C:2]1[N:3]=[C:4]2[CH:9]=[CH:8][CH:7]=[CH:6][N:5]2[C:10]=1[C:11]#[N:13]

Participants

6

Reactant 4

HCID 1049PyridineHCID 9845Trifluoroacetic anhydrideHCID 89061Imidazo(1,2-a)pyridine-3-carboxamide, 2-methyl-HCID 516892Sodium Bicarbonate

Product 1

HCID 882322-Methylimidazo[1,2-a]pyridine-3-carbonitrileYield 80%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

To a mixture of 2-methylimidazo[1,2-a]pyridine-3-carboxamide (3.50 g, 20 mmol) produced above, pyridine (4.85 mL, 60 mmol) and tetrahydrofuran (50 mL) was added dropwise a solution of trifluoroacetic anhydride (4.24 mL, 30 mmol) in tetrahydrofuran (10 mL) under ice-cooling. The mixture was stirred at room temperature for 1 hr, saturated aqueous sodium bicarbonate solution was added, and the mixture was extracted with ethyl acetate. The collected organic layer was washed with saturated brine and dried over anhydrous magnesium sulfate, and the insoluble material was filtered off. The filtrate was concentrated under reduced pressure, and the obtained residue was washed with ethyl acetate/diisopropyl ether to give the title compound (2.5 g, 80%) as a pale-brown solid.

Workup

  1. temperaturecooling
  2. extractionthe mixture was extracted with ethyl acetate
  3. washThe collected organic layer was washed with saturated brine
  4. dry with materialdried over anhydrous magnesium sulfate
  5. filtrationthe insoluble material was filtered off
  6. concentrationThe filtrate was concentrated under reduced pressure
  7. washthe obtained residue was washed with ethyl acetate/diisopropyl ether

Sources & evidence

ORD record
ord-b42b83ae79a942d0a5acaac369f8518e
Source dataset
uspto-grants-2015_09
Patent number
US09139589B2

Reaction notes

Loading…