Cesium carbonate → tert-Butyl {2-[1-(4-bromo-phenyl)piperidin-4-yl]ethyl}-carbamate

Participants

Reaction Steps

6.19 g (21.90 mmol) of 1-bromo-4-iodobenzene, 5.00 g (21.90 mmol) of tert-butyl (2-piperidin-4-ylethyl)carbamate, 9.98 g (60.66 mmol) of caesium carbonate and 0.54 g (0.88 mmol) of BINAP (2,2′-bis(diphenylphosphino)-1,1′-binaphthyl) suspended in 100 mL of toluene are placed under an inert atmosphere. 0.098 g (0.44 mmol) of palladium diacetate is then added. The reaction mixture is then refluxed for 6 hours. 0.045 g (0.20 mmol) of palladium diacetate and 0.25 g (0.40 mmol) of BINAP are added and the mixture is left to stir at reflux for 12 hours. The reaction medium is allowed to cool, and ethyl acetate and water are added. The aqueous phase is separated out and extracted twice with ethyl acetate, and the combined organic phases are washed with saturated aqueous sodium chloride solution and dried over sodium sulfate. After evaporating off the solvent, the residue obtained is purified by chromatography on silica gel, eluting with a 98/2/0.2 mixture of dichloromethane, methanol and 28% aqueous ammonia to give 1.66 g of expected product in the form of a white solid.

Provenance & Evidence