2-Bromopyridine → 1-(Pyridin-2-yl)piperazin-2-one

Participants

Reaction Conditions

Reaction Steps

A mixture of 4-benzyloxycarbonyl-1-methyl-pyrazin-2(1H)-one (3.0 g, 12.8 mmol), 2-bromopyridine (2.02 g, 12.8 mmol), palladium acetate (0.29 g, 1.28 mmol), xantphos (1.11 g, 1.92 mmol), cesium carbonate (6.26 g, 19.2 mmol) in anhydrous dioxane (13 mL) in a sealed vessel was heated in an oil bath at 110° C. for 6 hrs. The resultant reaction mixture was cooled to room temperature, diluted with dichloromethane, filtered, and concentrated under vacuum. The residual solid was subjected to column chromatography on silica gel eluting with a ethyl acetate-hexane gradient. Concentration of appropriate fractions provide the pyridine intermediate. A mixture of 4-benzyloxycarbonyl-1-pyridin-2-ylpiperazin-2-one (1.50 g, 4.94 mmol) and Pearlmans catalyst (0.7 g) in ethanol (50 mL) was stirred under an atmosphere of hydrogen (1 atm) at room temperature for one hour. The product mixture was filtered through a pad of Celite, and concentrated under vacuum to provide the titled compound.

Provenance & Evidence