1: 64 percent / m-chloroperbenzoic acid, Na2HPO4 / CH2Cl2 / 5 h / Ambient temperature 2: 80 percent / aq. K2CO3 / methanol / 0.25 h / Ambient temperature 3: 60 percent / NaH / dimethylformamide / 0.25 h / -20 °C 4: 50 percent / POCl3 / 1,2-dichloro-ethane / Heating View Scheme

1: 64 percent / m-chloroperbenzoic acid, Na2HPO4 / CH2Cl2 / 5 h / Ambient temperature 2: 80 percent / aq. K2CO3 / methanol / 0.25 h / Ambient temperature View Scheme