1: sodium tetrahydroborate; calcium chloride / methanol / 4 h / 20 - 30 °C 2: pyridinium p-toluenesulfonate / 24 h / 20 °C 3: triethylamine / toluene / 2 h / 5 - 20 °C 4: potassium carbonate / N,N-dimethyl-formamide / 4 h / 10 - 20 °C 5: hydrogenchloride / methanol; water / 1.5 h / 80 °C 6: triethylamine; thionyl chloride / dichloromethane / 0.17 h / 20 °C / |Cooling with ice 7: lithium chloride / N,N-dimethyl-formamide / 1.5 h / 80 °C View Scheme

Multi-step reaction with 2 steps 1: sodium tetrahydroborate; calcium chloride / methanol / 4 h / 20 - 30 °C2: pyridinium p-toluenesulfonate / 24 h / 20 °C