1: toluene / 2 h / |Reflux 2: N-bromosuccinmide; 2,2'-azo-bisisobutyronitrile / acetonitrile / 2 h / 90 °C / |Inert atmosphere 3: acetonitrile; ethanol / 12 h / 20 °C 4: dihydrogen peroxide / dimethyl sulfoxide / 20 °C 5: water / dimethyl sulfoxide / 20 °C View Scheme

1: acetonitrile; ethanol / 12 h / 20 °C 2: dihydrogen peroxide / dimethyl sulfoxide / 20 °C 3: water / dimethyl sulfoxide / 20 °C View Scheme

1: dihydrogen peroxide / dimethyl sulfoxide / 20 °C 2: water / dimethyl sulfoxide / 20 °C View Scheme

1: N-bromosuccinmide; 2,2'-azo-bisisobutyronitrile / acetonitrile / 2 h / 90 °C / |Inert atmosphere 2: acetonitrile; ethanol / 12 h / 20 °C 3: dihydrogen peroxide / dimethyl sulfoxide / 20 °C 4: water / dimethyl sulfoxide / 20 °C View Scheme