Triphenylarsine → 1-(4-Fluoro-phenyl)-6-(3-phenyl-3H-imidazol-4-yl)-1H-benzoimidazole

Participants

Reaction Conditions

Reaction Steps

To a flame-dried reaction flask were added commercially available 1-phenyl-1H-imidazole (50.5 mg, 0.35 mmol), palladium(II)acetate (7.86 mg, 35.0 μmol), cesium fluoride (106 mg, 0.7 mmol), triphenylarsine (21.4 mg, 70.0 μmol) and 6-bromo-1-(4-fluoro-phenyl)-1H-benzo[d]imidazole (intermediate G) (204 mg, 0.7 mmol). The reaction flask was evacuated, and backfilled with argon, and this sequence was repeated twice. Afterwards DMF (1.75 ml) was added successively under a stream of argon by syringe at room temperature. The resulting mixture was allowed to stir at 140° C. under an argon atmosphere for 48 h. Afterwards the reaction mixture was cooled to room temperature, poured into water (20 ml), extracted with ethyl acetate (2×30 ml) and washed with brine (20 ml). The combined organic layers were dried (MgSO4) and evaporated. The crude product was purified by flash chromatography on silica gel [dichloromethane/MeOH (0-3%)] and crystallization from dichloromethane/hexane to yield the title compound as an off-white solid (23 mg, 19%), MS (ISP) m/z=355.1 [(M+H)+], mp 216° C.

Provenance & Evidence