Citric Acid → Tert-butyl 2-(2-(benzyloxy)-5-(piperidin-1-yl)benzamido)-4-phenylbenzoate

Participants

Reaction Steps

Piperidine (0.040 mL), cesium carbonate (0.18 g), tris(dibenzylideneacetone)dipalladium(0) (2.5 mg), 2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (6.4 mg), and palladium(II) acetate (1.2 mg) were added to a toluene (2.3 mL) suspension of tert-butyl 2-(2-(benzyloxy)-5-bromobenzamido)-4-phenylbenzoate (0.15 g), followed by heating to reflux under a nitrogen atmosphere for 4 hours. The reaction mixture was cooled to room temperature, and then piperidine (0.040 mL), cesium carbonate (0.18 g), tris(dibenzylideneacetone)dipalladium(0) (2.5 mg), 2-dicyclohexylphosphino-2′,4′,6′-triisopropylbiphenyl (6.4 mg), and palladium(II) acetate (1.2 mg) were added thereto, followed by heating to reflux under a nitrogen atmosphere for 5 hours and 30 minutes. The reaction mixture was cooled to room temperature, and a 10% aqueous solution of citric acid and ethyl acetate were added thereto. The insoluble substance was removed by filtration. 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 [Kanto Chemical Co., Inc., silica gel 60 (spherical), eluent: 100-70% hexane/ethyl acetate] to obtain 0.13 g of tert-butyl 2-(2-(benzyloxy)-5-(piperidin-1-yl)benzamido)-4-phenylbenzoate as an orange oily substance.

Provenance & Evidence