Acetic acid, 2-(triphenylphosphoranylidene)-, ethyl ester → ethyl (2E)-3-{imidazo[1,2-a]pyridin-3-yl}prop-2-enoate

Temperature

65 °C

(Ethoxycarbonylmethylene)triphenylphosphorane (0.72 g, 2.05 mmol) was added to a solution of imidazo[1,2-a]pyridine-3-carbaldehyde (0.25 g, 1.71 mmol) in anhydrous tetrahydrofuran (THF) (20 mL) at room temperature. The reaction mixture was heated overnight at 65° C. After completion of the reaction as indicated by HPLC, the reaction mixture was diluted with ethyl acetate (EtOAc) (20 mL) and quenched with a saturated solution of ammonium chloride (10 mL). The organic layer was washed with water (3×20 mL) and brine (15 mL). It was dried over anhydrous Na2SO4, filtered and evaporated to get the crude product. This crude was purified by silica gel column chromatography using 50-80% EtOAc in Hexanes to provide pure (E)-ethyl 3-(imidazo[1,2-a]pyridin-3-yl)acrylate (0.19 g) as a white solid. ES+(M+H)+217.

1. customAfter completion of the reaction
2. customquenched with a saturated solution of ammonium chloride (10 mL)
3. washThe organic layer was washed with water (3×20 mL) and brine (15 mL)
4. dry with materialIt was dried over anhydrous Na2SO4
5. filtrationfiltered
6. customevaporated
7. customto get the crude product
8. customThis crude was purified by silica gel column chromatography

ORD record

ord-6a20cbc8aeab4f04a6be83cf4a024c43

Source dataset

uspto-grants-2015_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08957066B2