2-Bromo-4-(trifluoromethyl)pyridine → Tert-butyl 4-((diphenylmethyleneamino)methyl)-4-(4-(trifluoromethyl)pyridin-2-ylcarbamoyl)piperidine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

tert-butyl 4-carbamoyl-4-((diphenylmethyleneamino)methyl)piperidine-1-carboxylate (500 mg, 1.19 mmol), 2-bromo-4-(trifluoromethyl)pyridine (268 mg, 1.19 mmol), and cesium carbonate (541 mg, 1.66 mmol) were suspended in dioxane (2 mL) . The reaction was purged with nitrogen for 10 minutes then 9,9-Dimethyl-4,5-bis(diphenylphosphino)xanthene (30.9 mg, 0.05 mmol) and palladium(II) acetate (7.99 mg, 0.04 mmol) were added. The reaction was heated at 90 °C for 48 hours. The reaction was cooled to room temperature, diluted with DCM, filtered and concentrated. The crude product was purified by flash silica chromatography, elution gradient 0 to 40% EtOAc in isohexane. Pure fractions were evaporated to dryness to afford tert-butyl 4-((diphenylmethyleneamino)methyl)-4-(4-(trifluoromethyl)pyridin-2-ylcarbamoyl)piperidine-1-carboxylate (480 mg, 71.4 %) as a white solid.

Provenance & Evidence