tert-Butyl piperazine-1-carboxylate → tert-Butyl 4-(2-(ethoxycarbonyl)benzofuran-4-yl)piperazine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

ethyl 4-bromobenzofuran-2-carboxylate (2 g, 7.43 mmol), tert-butyl piperazine-1-carboxylate (1.384 g, 7.43 mmol), Tris(dibenzylideneacetone)dipalladium(0) (0.340 g, 0.37 mmol), 2-Dicyclohexylphosphino-2',4',6'-tri-iso-propyl-1,1'-biphenyl (0.354 g, 0.74 mmol) and CESIUM CARBONATE (3.15 g, 9.66 mmol) were heated under argon to 95 °C overnight. The mixture was allowed to cool. The mixture was diluted with EtOAc and the mixture was filtered through a pad of Celite. The filterate was collected and the solvent was removed by rotary evaporation. The crude product was added to a silica gel column and was eluted with 0-50% EtOAc in heptane. The collected fractions were combined and the solvent was removed to yield tert-butyl 4-(2-(ethoxycarbonyl)benzofuran-4-yl)piperazine-1-carboxylate (1.250 g, 44.9 %). MS (m+1) = 375.6. HPLC Peak RT = 3.29 minutes is product. Purity = 99%.

Provenance & Evidence