1.1: lithium aluminium tetrahydride / tetrahydrofuran / 1 h / Reflux 2.1: N-bromosuccinmide / N,N-dimethyl-formamide / 12 h / 0 - 20 °C 3.1: 1H-imidazole / dichloromethane / 1 h / 20 °C 4.1: n-butyllithium / tetrahydrofuran; hexane / 0.5 h / -78 °C / Inert atmosphere 4.2: 0.33 h / -78 - 0 °C / Inert atmosphere 5.1: titanium(IV) isopropylate / tetrahydrofuran / 4 h / Inert atmosphere; Reflux 6.1: lithium diisopropyl amide / tetrahydrofuran / 0.5 h / -78 °C / Inert atmosphere 6.2: 0.67 h / -78 - -60 °C / Inert atmosphere 7.1: hydrogenchloride; water / methanol / 2 h / 20 °C 8.1: potassium hydroxide / ethanol; water / 12 h / Reflux 9.1: pyridine / 20 °C 10.1: sodium hydride / tetrahydrofuran; mineral oil / 2 h / 20 °C 11.1: lithium aluminium tetrahydride / tetrahydrofuran / 2 h / Inert atmosphere; Reflux 12.1: boron trichloride / dichloromethane / -78 - 20 °C / Inert atmosphere View Scheme

1.1: lithium aluminium tetrahydride / tetrahydrofuran / 1 h / Reflux 2.1: N-bromosuccinmide / N,N-dimethyl-formamide / 12 h / 0 - 20 °C 3.1: 1H-imidazole / dichloromethane / 1 h / 20 °C 4.1: n-butyllithium / tetrahydrofuran; hexane / 0.5 h / -78 °C / Inert atmosphere 4.2: 0.33 h / -78 - 0 °C / Inert atmosphere 5.1: titanium(IV) isopropylate / tetrahydrofuran / 4 h / Inert atmosphere; Reflux 6.1: lithium diisopropyl amide / tetrahydrofuran / 0.5 h / -78 °C / Inert atmosphere 6.2: 0.67 h / -78 - -60 °C / Inert atmosphere 7.1: hydrogenchloride; water / methanol / 2 h / 20 °C 8.1: potassium hydroxide / ethanol; water / 12 h / Reflux 9.1: pyridine / 20 °C 10.1: sodium hydride / tetrahydrofuran; mineral oil / 2 h / 20 °C 11.1: lithium aluminium tetrahydride / tetrahydrofuran / 2 h / Inert atmosphere; Reflux 12.1: boron trichloride / dichloromethane / -78 - 20 °C / Inert atmosphere View Scheme