反应详情

To a solution of 2-amino-isonicotinic acid methyl ester (1 eq.) and chloroacetaldehyde (45% w/w in water) (4.5 eq.) in ethanol was added NaHCO3 (1.7 eq.). The reaction mixture was refluxed for 15 h and the solvents removed under reduced pressure. The residue was partitioned between water and EtOAc, the organic layer was washed with a saturated aqueous solution of Na2CO3 and brine, dried over MgSO4, filtered and concentrated under reduced pressure. The crude was purified by chromatography on silica gel (elution with DCM/MeOH: 100/0 to 98/2) to afford imidazo[1,2-a]pyridine-7-carboxylic acid methyl ester.

1. temperatureThe reaction mixture was refluxed for 15 h
2. customthe solvents removed under reduced pressure
3. customThe residue was partitioned between water and EtOAc
4. washthe organic layer was washed with a saturated aqueous solution of Na2CO3 and brine
5. dry with materialdried over MgSO4
6. filtrationfiltered
7. concentrationconcentrated under reduced pressure
8. customThe crude was purified by chromatography on silica gel (elution with DCM/MeOH: 100/0 to 98/2)