1: 84 percent / Jones reagent / acetone / 4 h / 0 °C 2: 71 percent / diethyl ether / 0.08 h 3: 1) Mg / 1) ether, 2) ether, -20 deg C, 3 h 4: 71 percent / p-toluenesulfonic acid / toluene / 4 h / Heating View Scheme