1: With toluene-4-sulfonic acid T=125°C; 10 h; 2: With hydrogenchloride in water 1 h; Heating / reflux; 3: in water pH=7;

platinum(IV) oxide; 10 palladium on activated carbon; hydrogen; sodium hydroxide in water P=2585.81 Torr; 0.5 h;

iron; ytterbium(III) triflate T=75°C; 3 h;

1: 52 percent / 3 h / 140 - 150 °C 2: 70 percent / KMnO4, Na2CO3 / H2O / 2 h / Heating 3: Heating View Scheme

1: 70 percent / KMnO4, Na2CO3 / H2O / 2 h / Heating 2: Heating View Scheme

1.1: 1,3-dibromo-5,5-dimethyl-hydantoin / dichloromethane / 0.5 h / -45 °C 1.2: -45 - 22 °C 2.1: sulfuric acid; nitric acid / -10 - 22 °C 3.1: sulfuric acid / 2 h / 22 °C 3.2: 22 °C 4.1: hydrogenchloride; tin(ll) chloride / water / 0 - 100 °C 5.1: 1 h / Erfllectrochemical reaction 6.1: 10 palladium on activated carbon; platinum(IV) oxide; hydrogen; sodium hydroxide / water / 0.5 h / 2585.81 Torr View Scheme

1.1: sulfuric acid; nitric acid / -10 - 22 °C 2.1: sulfuric acid / 2 h / 22 °C 2.2: 22 °C 3.1: hydrogenchloride; tin(ll) chloride / water / 0 - 100 °C 4.1: 1 h / Erfllectrochemical reaction 5.1: 10 palladium on activated carbon; platinum(IV) oxide; hydrogen; sodium hydroxide / water / 0.5 h / 2585.81 Torr View Scheme

1: 1 h / Erfllectrochemical reaction 2: 10 palladium on activated carbon; platinum(IV) oxide; hydrogen; sodium hydroxide / water / 0.5 h / 2585.81 Torr View Scheme

1: hydrogenchloride; tin(ll) chloride / water / 0 - 100 °C 2: 1 h / Erfllectrochemical reaction 3: 10 palladium on activated carbon; platinum(IV) oxide; hydrogen; sodium hydroxide / water / 0.5 h / 2585.81 Torr View Scheme

Heating;