Bromobenzene → Benzyl 2,4-diphenylpiperazine-1-carboxylate

Participants

Reaction Steps

A solution of benzyl 2-phenylpiperazine-1-carboxylate (0.17 g, 0.58 mmol), bromobenzene (0.37 g, 2.37 mmol), tris(dibenzylideneacetone)dipalladium(0) (0.06 g, 0.06 mmol), sodium tert-butoxide (0.20 g, 2.0 mmol) and 2-dicyclohexylphosphino-2′-(N,N-dimethylamino)biphenyl (0.25 g, 0.64 mmol) in benzene (20 mL) was heated to 80° C. for 4.5 hours. After cooling, the reaction was diluted with ethyl acetate (60 mL), and washed with water (2×30 mL), then dried over anhydrous sodium sulfate, filtered and concentrated. The residue was purified by silica gel column chromatography (ethyl acetate/hexanes, 1:4) to give benzyl 2,4-diphenylpiperazine-1-carboxylate (0.17 g, 79% yield) as an oil. MS (EI) for C24H24N2O2: 373 (MH+).

Provenance & Evidence