1: pyridinium dichromate / CH2Cl2 / 6 h / Ambient temperature 2: 34 mg / 1.) m-chlorperbenzoic acid, p-TsOH; 2.) m-chlorperbenzoic acid / CHCl3 / Ambient temperature; 1.) 48 h; 2.) 92 h 3: 2 N NaOH / methanol; H2O / 18 h / Heating View Scheme