1: pyridine / 2 h / Ambient temperature 2: KBr, 18-crown-6 ether / acetone / Heating 3: 1.) Mg, 1,2-dibromoethane / 1.) ether, 1 h, 2.) ether, 5 deg C - 9 deg C, 4 h 4: 1.32 g / 30percent aq. H2O2, 6 N aq. NaOH / ethanol / 3 h / 20 °C View Scheme