1: 88 percent / m-chloroperbenzoic acid / CH2Cl2 / 24 h / Ambient temperature 2: 24 h / 140 °C 3: 1 M aq. NaHCO3 / acetone / 2 h / 40 °C View Scheme

With  3-chloro-benzenecarboperoxoic acid in  dichloromethane 24 h;  Ambient temperature;