1.1: tetrahydrofuran; hexanes / 2 h / -78 °C / Inert atmosphere 1.2: 2 h / -78 - 20 °C / Inert atmosphere 2.1: RuCl2(tricyclohexylphosphine)2(benzylidene) / dichloromethane / 12 h / 30 °C / Inert atmosphere 2.2: 12 h / 20 °C / Inert atmosphere 3.1: 2,2'-azo-bisisobutyronitrile; iodine / dichloromethane / 12 h / 20 °C / Inert atmosphere 3.2: 0.25 h / 20 °C / Inert atmosphere 3.3: 5 h / Inert atmosphere; Reflux 4.1: thionyl chloride / 5 h / 50 °C / Inert atmosphere 4.2: 4 h / Inert atmosphere 5.1: 4-(N,N-dimethlyamino)pyridine; triethylamine / dichloromethane / 12 h / 20 °C / Inert atmosphere 5.2: Inert atmosphere 6.1: hydrogenchloride / methanol / 0.08 h / 20 °C / Inert atmosphere View Scheme

trifluoroacetic acid in dichloromethane T=22°C; 12 h;