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

Participants

Reaction Conditions

Reaction Steps

(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.

Provenance & Evidence