Citric Acid → Tert-butyl 4-(4-((tert-butoxycarbonyl)(methyl)amino)phenyl)-2-(5-phenylpyridine-3-carboxamido)benzoate

Participants

Reaction Steps

Water (0.60 mL), sodium carbonate (88 mg), tert-butyl methyl(4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl)carbamate (0.13 g), and bis(triphenylphosphine)palladium(II) dichloride (5.0 mg) were added to an ethylene glycol dimethyl ether (2.0 mL) solution of tert-butyl 4-bromo-2-(5-phenylpyridine-3-carboxamido)benzoate (0.15 g), followed by heating to reflux under a nitrogen atmosphere for 1 hour. The reaction mixture was cooled to room temperature, and then a 10% aqueous solution of citric acid and ethyl acetate were added thereto. The organic layer was separated, washed with a saturated aqueous solution of sodium chloride, and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The obtained residue was purified by silica gel column chromatography [eluent: 95-85% hexane/ethyl acetate] to obtain 0.16 g of tert-butyl 4-(4-((tert-butoxycarbonyl)(methyl)amino)phenyl)-2-(5-phenylpyridine-3-carboxamido)benzoate as a white solid.

Provenance & Evidence