1.1: toluene-4-sulfonic acid / benzene / 3 h / 20 °C 1.2: 16.5 h / 20 °C / Reflux 2.1: dihydrogen peroxide / 1,1,1-trifluoropropanone / dichloromethane; acetonitrile; water / 2 h / 20 °C / aqueous K2C03 / EDTA-Na2 buffer 3.1: Cu(BF4)2*xH2O / dichloromethane / 2 h / 20 °C 4.1: ethanol / 1 h / 20 °C 4.2: 72 h / 110 °C View Scheme