1,2-Dimethoxyethane → 5-(3-Fluoro-4-nitrophenyl)-6-(4-fluorophenyl)-imidazo[2,1-b]oxazole

Participants

Reaction Conditions

Reaction Steps

A mixture of 6-(4-fluorophenyl)-5-iodo-imidazo[2,1-b]oxazole (10.0 g, 27.4 mmol; Preparation #A.1), 2-(3-fluoro-4-nitrophenyl)-4,4,5,5-tetramethyl-[1,3,2]dioxaborolane (11.9 g, 41.1 mmol; Preparation #B.1), Cs2CO3 (28.6 g, 87.8 mmol), tetrakis(triphenylphosphine)palladium(0) (3.17 g, 2.74 mmol; Strem), DME (150 mL) and water (30.0 mL) was added to a flask with screw-thread top. The flask was sealed and heated at about 100° C. for about 16 h. After cooling to ambient temperature the reaction was concentrated under reduced pressure to remove organic solvent. The resulting mixture was diluted with water (200 mL) and EtOAc (200 mL) then filtered to remove insoluble material. The layers were separated and the aqueous layer was extracted with additional EtOAc (2×200 mL). The combined organic layers were washed with brine, dried over Na2SO4, decanted, and concentrated. The crude material was purified by silica gel chromatography using DCM to give the title compound (7.80 g, 78%): LC/MS (Table 1, Method b) Rt=2.19 min; MS m/z: 342.1 (M+H)+.

Provenance & Evidence