Water → 3-(4-Fluoro-phenyl)-6-[2-(4-fluoro-phenyl)-2H-pyrazol-3-yl]-imidazo[1,2-a]pyridine

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Reaction Steps

To a mixture of 6-bromo-3-(4-fluorophenyl)-imidazo[1,2-a]pyridine (intermediate E) (100 mg, 344 μmol) and 1-(4-fluoro-phenyl)-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1H-pyrazole (intermediate A) (119 mg, 412 μl) in 1,2-dimethoxyethane (2 ml), was added 1M Na2CO3 (859 μl, 859 μmol), and the reaction mixture was purged with argon for 10 min in an ultrasonic bath. Afterwards tetrakis(triphenylphosphine)palladium(0) (39.7 mg, 34.4 μmol) was added, and the stirred reaction mixture was heated under reflux conditions for 17 h. The reaction mixture was cooled to room temperature, poured into water (20 ml) and extracted with ethyl acetate (2×20 ml). The combined organic layers were washed with brine (20 ml), dried (MgSO4) and evaporated. The crude material (190 mg) was further purified by flash chromatography on silica gel (dichloromethane/MeOH, 0-20%) and trituration (diethyl ether) to yield the title compound as an off-white solid (40 mg, 31%), MS (ISP) m/z=373.4 [(M+H)+], mp 172° C.

Provenance & Evidence