1: sulfuric acid / dichloromethane / 0 °C / Inert atmosphere 2: toluene / 4 h / 80 °C / Inert atmosphere 3: potassium carbonate / ethanol / 14 h / Inert atmosphere; Reflux View Scheme

1: With bis-triphenylphosphine-palladium(II) chloride; copper(l) iodide in dichloromethane 0.5 h; 2: With diethylamine in dichloromethane T=20°C; 16 h;

1.1: trifluoroacetic acid / dichloromethane / 0 - 20 °C / Inert atmosphere 2.1: hydrogenchloride; acetic acid; sodium nitrite / water / 0 - 5 °C / Inert atmosphere 2.2: 0 - 20 °C / Inert atmosphere 3.1: copper(l) iodide; bis-triphenylphosphine-palladium(II) chloride / dichloromethane / 0.5 h / Inert atmosphere 3.2: 16 h / 20 °C / Inert atmosphere View Scheme

1.1: tert.-butyl lithium / tetrahydrofuran; pentane / 3.33 h / -78 - -30 °C / Inert atmosphere 1.2: 0.83 h / -78 °C / Inert atmosphere 2.1: trifluoroacetic acid / dichloromethane / 0 - 20 °C / Inert atmosphere 3.1: hydrogenchloride; acetic acid; sodium nitrite / water / 0 - 5 °C / Inert atmosphere 3.2: 0 - 20 °C / Inert atmosphere 4.1: copper(l) iodide; bis-triphenylphosphine-palladium(II) chloride / dichloromethane / 0.5 h / Inert atmosphere 4.2: 16 h / 20 °C / Inert atmosphere View Scheme

1.1: tert.-butyl lithium / tetrahydrofuran; pentane / 3.33 h / -78 - -30 °C / Inert atmosphere 1.2: 0.83 h / -78 °C / Inert atmosphere 2.1: trifluoroacetic acid / dichloromethane / 0 - 20 °C / Inert atmosphere 3.1: hydrogenchloride; acetic acid; sodium nitrite / water / 0 - 5 °C / Inert atmosphere 3.2: 0 - 20 °C / Inert atmosphere 4.1: copper(l) iodide; bis-triphenylphosphine-palladium(II) chloride / dichloromethane / 0.5 h / Inert atmosphere 4.2: 16 h / 20 °C / Inert atmosphere View Scheme

1: With hydrogenchloride in 1,4-dioxane; water T=20 - 60°C; 16 h; 2: With sodium carbonate in 1,4-dioxane; dichloromethane; water 2 h;