2-Bromopyridine → ethyl 5-(2,4-dichloro-5-(pyridin-2-yl)benzamido)-1-phenyl-1H-pyrazole-3-carboxylate

Participants

Reaction Steps

To the solution of ethyl 5-(2,4-dichloro-5-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)benzamido)-1-phenyl-1H-pyrazole-3-carboxylate in dioxane (Preparation 4, 675 mg, 1.27 mmol) was added water (2.2 mL), 2-bromopyridine (302 mg, 1.91 mmol) and K2CO3 (352 mg, 2.546 mmol). The reaction was degassed for 10 minutes before the addition of tetrakis(triphenylphosphine)palladium(0) (147 mg, 0.127 mmol) and heating at reflux for 2 hours. The reaction was cooled and concentrated in vacuo. The residue was purified using silica gel chromatography eluting with 20-50% EtOAc in heptanes to afford the title compound (128 mg, 21%).

Provenance & Evidence