Multi-step reaction with 5 steps 1.1: magnesium / diethyl ether / |Inert atmosphere; |Reflux1.2: 0 °C / |Inert atmosphere2.1: trifluoroacetic acid / dichloromethane / 0.25 h / 20 °C / |Inert atmosphere2.2: 1 h / 20 °C / |Inert atmosphere2.3: 0 °C3.1: copper(l) iodide / tetrahydrofuran / 4 h / |Inert atmosphere; |Reflux3.2: 3 h / 0 - 20 °C / |Inert atmosphere3.3: 1 h / 50 - 60 °C4.1: pyridine / dichloromethane / 0 - 10 °C / |Inert atmosphere5.1: ethanol / 0.5 h / |Reflux