1: 67.1 percent / pyridinium dichromate / CH2Cl2; acetic anhydride / 2 h / Heating 2: 85 percent / diethyl ether / 1 h / Ambient temperature 3: 71 percent / pyridinium dichromate / CH2Cl2; acetic anhydride / 2 h / Heating 4: 75 percent / aluminium chloride, sodium chloride / 0.08 h / 180 - 190 °C View Scheme

With  lithium aluminium tetrahydride; aluminium trichloride in  diethyl ether T=5°C; 1 h;   

Multi-step reaction with 4 steps 1: 90 percent / t-butyl hydroperoxide / VO(acac)2 / 4 h / Ambient temperature2: 83 percent / LAH / tetrahydrofuran / 4 h / Ambient temperature3: 69 percent / p-toluenesulphonic acid / acetonitrile / 0.5 h / 0 deg C to room temperature4: 86 percent / aluminium chloride, LAH / diethyl ether / 1 h / 5 °C  

Multi-step reaction with 2 steps 1: 69 percent / p-toluenesulphonic acid / acetonitrile / 0.5 h / 0 deg C to room temperature2: 86 percent / aluminium chloride, LAH / diethyl ether / 1 h / 5 °C  

Multi-step reaction with 3 steps 1: 83 percent / LAH / tetrahydrofuran / 4 h / Ambient temperature2: 69 percent / p-toluenesulphonic acid / acetonitrile / 0.5 h / 0 deg C to room temperature3: 86 percent / aluminium chloride, LAH / diethyl ether / 1 h / 5 °C  

With  dipyridinium dichromate in  dichloromethane; acetic anhydride 2 h;  Heating;   

Multi-step reaction with 2 steps 1: 67.1 percent / pyridinium dichromate / CH2Cl2; acetic anhydride / 2 h / Heating2: 85 percent / diethyl ether / 1 h / Ambient temperature  

Multi-step reaction with 3 steps 1: 67.1 percent / pyridinium dichromate / CH2Cl2; acetic anhydride / 2 h / Heating2: 85 percent / diethyl ether / 1 h / Ambient temperature3: 71 percent / pyridinium dichromate / CH2Cl2; acetic anhydride / 2 h / Heating