sodium hydroxide in methanol T=20°C; 2 h; Yield given;

1: 82 percent / m-perbenzoic acid / CH2Cl2 / 12 h 2: Mg, 1,2-dibromoethane / diethyl ether / 1 h / Ambient temperature 3: 10percent aq. NaOH / methanol / 2 h / 20 °C View Scheme

1: Mg, 1,2-dibromoethane / diethyl ether / 1 h / Ambient temperature 2: 10percent aq. NaOH / methanol / 2 h / 20 °C View Scheme