3-chloro-benzenecarboperoxoic acid in dichloromethane T=-60 - -40°C; Yield given;

1: m-chloroperoxybenzoic acid / CH2Cl2 / -60 - -40 °C 2: 1) lithium diisopropylamide / 1) THF, -70 deg C, 20 min, 2) THF, -70 deg C, 10 min 3: 30percent aq. KOH / methanol / 1 h / Ambient temperature 4: 75 percent / sodium benzeneselenolate / ethanol / 16 h / Heating View Scheme

1: m-chloroperoxybenzoic acid / CH2Cl2 / -60 - -40 °C 2: 1) lithium diisopropylamide / 1) THF, -70 deg C, 20 min, 2) THF, -70 deg C, 10 min 3: 30percent aq. KOH / methanol / 1 h / Ambient temperature View Scheme