2-Bromoanisole → Tert-butyl 4-(2-methoxyphenyl)piperazine-1-carboxylate

Participants

Reaction Conditions

Reaction Steps

TRIS(DIBENZYLIDENEACETONE)DIPALLADIUM(0) (0.059 g, 0.06 mmol) and 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (0.080 g, 0.13 mmol) were mixed in toluene (10 mL) and degessed at 90 °C for 10 mins. The mixture was then cooled and 1-bromo-2-methoxybenzene (0.400 mL, 3.21 mmol), sodium 2-methylpropan-2-olate (0.493 g, 5.13 mmol) and tert-butyl piperazine-1-carboxylate (0.597 g, 3.21 mmol) were added. The resulting mixture was stirred at 100 °C for 16 hours under nitrogen. The reaction mixture was filtered through celite and the filtrate concentrated. The crude product was purified by flash silica chromatography, elution gradient 20 to 100% EtOAc in heptane. Pure fractions were evaporated to dryness to afford tert-butyl 4-(2-methoxyphenyl)piperazine-1-carboxylate (0.585 g, 62.4 %) as a yellow oil which crystallised on standing.

Provenance & Evidence