1: 92 percent / CrO3, pyridine / 4 h / Ambient temperature 2: 9 percent / aq. NH3 / 20 h / 190 °C View Scheme

1: 80 percent / m-chloroperbenzoic acid / CH2Cl2 / 1.) 5 - 10 deg C, 30 min, 2.) RT, 2.5 h 2: 89 percent / pyridine / 3 h / 0 °C View Scheme

3-chloro-benzenecarboperoxoic acid in dichloromethane 1.) 5 - 10 deg C, 30 min, 2.) RT, 2.5 h;

1: 80 percent / m-chloroperbenzoic acid / CH2Cl2 / 1.) 5 - 10 deg C, 30 min, 2.) RT, 2.5 h 2: 89 percent / pyridine / 3 h / 0 °C 3: 78 percent / acetonitrile / 16 h / 150 °C 4: 95 percent / diethyl ether / 1.5 h / Ambient temperature View Scheme

With  1-hydroxy-3H-benz[d][1,2]iodoxole-1,3-dione in  ethyl acetate T=30 - 75°C;