Cesium carbonate → HCID 68671838, compound

Participants

Reaction Conditions

Reaction Steps

2-(5-Bromo-2-fluoro-phenyl)-benzoimidazole-1-carboxylic acid tert-butyl ester (2.52 g, 6.5 mmol), piperazine-1-carboxylic acid tert-butyl ester (1.56 g, 8.40 mmol) and cesium carbonate (10.50 g, 32.20 mmol) were placed into a dry 500 mL round bottom flask under nitrogen and dry toluene (140 mL) was added. At the same time palladium acetate (0.29 g, 1.30 mmol) and BINAP (1.20 g, 1.93 mmol) were placed into a dry 250 mL round bottom flask under nitrogen and dry toluene (140 mL) was added. After 10 minutes the suspension containing BINAP and Palladium acetate was added to the 500 mL round bottom flask. The reaction mixture was heated at 85° C. overnight under nitrogen and cooled to room temperature. The mixture was filtered and the insoluble material was washed with EtOAC (3×20 mL). The organic solution was concentrated under reduced pressure and crude was purified by flash chromatography (eluent: cyclohexane:AcOEt gradient from 100% of cyclohexane to cyclohexane 4:AcOEt 1) to afford 2.48 g of the title compound (76%).

Provenance & Evidence