203661-71-6

1558037-99-2

203661-71-6

1.21 mol) and zinc powder (Zn, 79.1 g, 1.21 mol). The reaction mixture was stirred at room temperature for 8 hours. After completion of the reaction, the mixture was treated with distilled water (H2O) and extracted with ethyl acetate (EtOAc). The organic layers were combined, washed with saturated brine, dried over anhydrous sodium sulfate (Na2SO4) and concentrated under reduced pressure. The crude product was purified by fast column chromatography (silica gel, eluent: petroleum ether to 25% ethyl acetate in petroleum ether solution) to afford the target product R-5 (19 g, 69% yield).