1: With monopotassium carbonate in acetonitrile 10 h; Heating / reflux; 2: With sodium tetrahydroborate in ethyl acetate T=20°C; 3 h;

Red-Al in toluene T=50°C; 10 h; Inert atmosphere;

1: caesium carbonate; palladium diacetate; PCy3∙HBF4; 2,2,2-trimethylacetic acid / toluene / 12 h / 110 °C / |Inert atmosphere 2: Red-Al / toluene / 10 h / 50 °C / |Inert atmosphere View Scheme

1.1: diborane / tetrahydrofuran / 8 h / |Inert atmosphere; |Reflux 2.1: sodium hydride / 1,2-dichloro-ethane / 0 °C / |Inert atmosphere 2.2: 0 - 20 °C / |Inert atmosphere 3.1: caesium carbonate; palladium diacetate; PCy3∙HBF4; 2,2,2-trimethylacetic acid / toluene / 12 h / 110 °C / |Inert atmosphere 4.1: Red-Al / toluene / 10 h / 50 °C / |Inert atmosphere View Scheme

1: lithium hexamethyldisilazane / |Inert atmosphere 2: lithium aluminium tetrahydride / tetrahydrofuran / |Inert atmosphere View Scheme

lithium aluminium tetrahydride in tetrahydrofuran Inert atmosphere;

triethylamine in dichloromethane; toluene T=0°C; 1 h;

sodium nitrate; sulfuric acid in water T=-10 - -5°C; 1 h;

1: NaNO3 / sulfuric acid 2: sodium hydrogencarbonate / dichloromethane 3: hydrogenchloride / Pd-C / methanol; ethanol View Scheme