Potassium Carbonate → Ethyl 6-fluoro-8-(1,3-oxazol-5-yl)imidazo[1,2-a]pyridine-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of ethyl 8-bromo-6-fluoroimidazo[1,2-a]pyridine-3-carboxylate (1.0 g), 5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-2-(triisopropylsilyl)oxazole (1.2 g), tetrakis(triphenylphosphine)palladium(0) (403 mg) and potassium carbonate (963 mg) in DME/water (15/4 mL) was stirred with microwave irradiation at 120° C. for 40 min. The reaction mixture was diluted with water, and extracted with ethyl acetate. The extract was dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was dissolved in THF (15 mL), and 1N hydrochloric acid (4 mL) was added thereto. The reaction mixture was stirred at room temperature for 2 hr, saturated aqueous sodium bicarbonate solution was added thereto, and the mixture was extracted with ethyl acetate. The extract was dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate/hexane), and the obtained solid was recrystallized from ethyl acetate/hexane to give the title compound (188 mg).

Provenance & Evidence