CC(C)(C)OC(=O)N1CCNCC1.Clc1ccc(OCc2ccccc2)cn1>CC(C)(C)[O-].Cc1ccccc1.O=C(/C=C/c1ccccc1)/C=C/c1ccccc1.O=C(/C=C/c1ccccc1)/C=C/c1ccccc1.[Na+].[Pd].c1ccc(P(c2ccccc2)c2ccc3ccccc3c2-c2c(P(c3ccccc3)c3ccccc3)ccc3ccccc23)cc1>CC(C)(C)OC(=O)N1CCN(c2ccc(OCc3ccccc3)cn2)CC1BIS(DIBENZYLIDENEACETONE)PALLADIUM (0.055 g, 0.10 mmol) was added to tert- butyl piperazine-1-carboxylate (1.952 g, 10.48 mmol), 5-(benzyloxy)-2-chloropyridine (2.093 g, 9.53 mmol), 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (0.059 g, 0.10 mmol) and sodium 2-methylpropan-2-olate (1.282 g, 13.34 mmol) in toluene (30 mL) at 20ºC under nitrogen. The resulting solution was stirred at 80 °C for 16 hours then cooled to room temperature. The reaction mixture was filtered through celite, filtrate partitioned between ethyl acetate (100 mL) and water (100 mL). The organic phase was dried (Na2SO4), filtered and evaporated to give a brown gum. The crude product was purified by flash silica chromatography, elution gradient 0 to 20% EtOAc in isohexane. Pure fractions were evaporated to dryness to afford tert-butyl 4-(5-(benzyloxy)pyridin-2-yl)piperazine-1-carboxylate (2.420 g, 68.7 %) as a yellow solid.
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