1.1: Mg / diethyl ether / 20 °C 1.2: 95 percent / (dppp)NiCl2 / diethyl ether / Heating 2.1: ozone / CH2Cl2; methanol / 0.5 h / -78 °C 2.2: 96 percent / dimethylsulfide / CH2Cl2; methanol / -78 - 20 °C 3.1: 66 percent / magnesium sulfate; potassium permanganate / acetone / 2 h / 20 °C View Scheme