1: 91 percent / CAN / H2O; acetonitrile / 1.5 h / 0 °C 2: 99 percent / imidazole / dimethylformamide / 14 h / Ambient temperature 3: 100 percent / H2 / 5percent Pd-C / ethyl acetate / 20 h / Ambient temperature 4: 91 percent / pyridinium dichromate / dimethylformamide / 15 h / Ambient temperature View Scheme

With  ammonium cerium(IV) nitrate in  water; acetonitrile T=0°C;   

Multi-step reaction with 2 steps 1: 91 percent / CAN / H2O; acetonitrile / 1.5 h / 0 °C2: 99 percent / imidazole / dimethylformamide / 14 h / Ambient temperature