1: sodium hydroxide / 2 h / 0 - 20 °C 2: lithium chloride / N,N-dimethyl-formamide / 6 h / |Reflux 3: sodium carbonate; sodium dithionite; water / 1 h / 20 °C 4: trifluoroacetic acid / toluene / 6 h / 80 °C View Scheme

1: sodium hydroxide / 2 h / 0 - 20 °C 2: lithium chloride / N,N-dimethyl-formamide / 6 h / |Reflux 3: sodium carbonate; sodium dithionite; water / 1 h / 20 °C 4: trifluoroacetic acid / toluene / 6 h / 80 °C 5: triethylamine; pyridine / 2 h / 20 °C / |Inert atmosphere View Scheme

1: sodium hydroxide / 2 h / 0 - 20 °C 2: lithium chloride / N,N-dimethyl-formamide / 6 h / |Reflux 3: sodium carbonate; sodium dithionite; water / 1 h / 20 °C 4: trifluoroacetic acid / toluene / 6 h / 80 °C View Scheme

1: sodium hydroxide / 2 h / 0 - 20 °C 2: lithium chloride / N,N-dimethyl-formamide / 6 h / |Reflux 3: sodium carbonate; sodium dithionite; water / 1 h / 20 °C 4: trifluoroacetic acid / toluene / 6 h / 80 °C 5: triethylamine; pyridine / 2 h / 20 °C / |Inert atmosphere 6: hydrogenchloride; water / 3 h / 20 - 70 °C View Scheme

nitric acid T=-5 - 5°C; 10 h;

1.1: hydroxylamine hydrochloride; sodium hydroxide; water / ethanol / 4 h / 5 °C 2.1: acetic anhydride / 2 h / 110 °C 3.1: magnesium / tetrahydrofuran / 0.5 h / 40 °C 3.2: 1 h / 40 °C 4.1: nitric acid / dichloromethane / 12 h / 10 - 20 °C View Scheme

1.1: acetic anhydride / 2 h / 110 °C 2.1: magnesium / tetrahydrofuran / 0.5 h / 40 °C 2.2: 1 h / 40 °C 3.1: nitric acid / dichloromethane / 12 h / 10 - 20 °C View Scheme

1.1: magnesium / tetrahydrofuran / 0.5 h / 40 °C 1.2: 1 h / 40 °C 2.1: nitric acid / dichloromethane / 12 h / 10 - 20 °C View Scheme

1: sodium hydroxide / 2 h / 0 - 20 °C 2: lithium chloride / N,N-dimethyl-formamide / 6 h / |Reflux View Scheme