1: 93 percent / aq. NaIO4 / methanol / 20 h / Ambient temperature 2: 68 percent / TFAA / benzene / 18 h / Ambient temperature 3: 76 percent / NaBH4, NiCl2*6H2O / methanol; tetrahydrofuran / 0.5 h / Ambient temperature 4: 78 percent / 10percent NaOH / ethanol / 18 h / Heating View Scheme

sodium periodate in methanol 20 h; Ambient temperature;

sodium hydrogencarbonate; 3-chloro-benzenecarboperoxoic acid in dichloromethane T=-30°C; 2.5 h;