1: 89 percent / m-chloroperbenzoic acid / CH2Cl2 / 0.17 h / 0 °C 2: 65 percent / thionyl chloride / CH2Cl2 / 1.5 h / Ambient temperature; further reagent acetyl chloride View Scheme

With  3-chloro-benzenecarboperoxoic acid in  dichloromethane T=0°C; 0.166667 h;