trifluoroacetic acid in dichloromethane T=20°C; 3 h;

iron(III) chloride; carbon; hydrazine in methanol T=80°C;

diphenyl phosphoryl azide; triethylamine in toluene; tert-butyl alcohol T=80 - 100°C; 20 h;

hydrogenchloride in ethanol; water Reflux;

N-bromosuccinmide in 1,4-dioxane T=20°C;

1.1: sodium hydroxide / ethanol / Reflux 2.1: sodium hydroxide / N,N-dimethyl-formamide / 1 h / 20 °C / Inert atmosphere 2.2: 2 h / 20 °C / Inert atmosphere 3.1: sodium hydroxide / N,N-dimethyl-formamide / 2 h / 60 °C / Inert atmosphere 4.1: hydrogenchloride / ethanol; water / Reflux View Scheme

1: sodium hydroxide / N,N-dimethyl-formamide / 2 h / 60 °C / Inert atmosphere 2: hydrogenchloride / ethanol; water / Reflux View Scheme

1.1: sodium hydroxide / N,N-dimethyl-formamide / 1 h / 20 °C / Inert atmosphere 1.2: 2 h / 20 °C / Inert atmosphere 2.1: sodium hydroxide / N,N-dimethyl-formamide / 2 h / 60 °C / Inert atmosphere 3.1: hydrogenchloride / ethanol; water / Reflux View Scheme

1.1: lithium diisopropyl amide / tetrahydrofuran / -78 °C 2.1: sodium hydroxide / ethanol / Reflux 3.1: sodium hydroxide / N,N-dimethyl-formamide / 1 h / 20 °C / Inert atmosphere 3.2: 2 h / 20 °C / Inert atmosphere 4.1: sodium hydroxide / N,N-dimethyl-formamide / 2 h / 60 °C / Inert atmosphere 5.1: hydrogenchloride / ethanol; water / Reflux View Scheme