3,5-Dibromopyridine → 1-[4-(5-Bromo-3-pyridinyl)piperazin-1-yl]ethanone

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

3,5-dibromopyridine (1.233 g, 5.20 mmol), 1-(piperazin-1-yl)ethanone (0.734 g, 5.73 mmol), PdOAc2 (0.117 g, 0.52 mmol), XANTPHOS (0.361 g, 0.62 mmol), Cs2CO3 (5.09 g, 15.61 mmol), 1,4-dioxane as added to a 10 mL microwave vial. This was degassed and refilled with N2 and then heated at 140 °C in microwave for 1h. LCMS showed reaction done with the peak at Rf1.24 showed a fragment mass of 284. Evaporated solvent. Residue purified by ISCO (0-20% MeOH in EtOAc )to get the desired product 1-(4-(5-bromopyridin-3-yl)piperazin-1-yl)ethanone (0.470 g, 31.8 %). Trial # 1: 3,5-dibromopyridine (407 mg, 1.72 mmol), 1-(piperazin-1-yl)ethanone (231 mg, 1.81 mmol), PdOAc2 (38.6 mg, 0.17 mmol), XANTPHOS (119 mg, 0.21 mmol), Cs2CO3 (1681 mg, 5.16 mmol), 1,4-dioxane as added to a 10 mL microwave vial. This was degassed and refilled with N2 and then heated at 140 °C in microwave for 1h. LCMS showed reaction done with the peak at Rf1.22 showed a fragment mass of 284. Evaporated solvent. Residue purified by ISCO (0-20% MeOH in EtOAc )to get the desired product 1-(4-(5-bromopyridin-3-yl)piperazin-1-yl)ethanone (118mg, 24%).

Herkunft & Nachweise