1: p-toluenesulfonic acid / 15 h / Heating 2: 1.) Mg, ethylene dibromide, 2.) B2H6, 3.) aq. NaOH, H2O2 3: NaBH4 / ethanol / 0.5 h 4: p-toluenesulfonic acid / benzene / 1 h / Heating 5: pyridine / 3 h 6: 2,3-dichloro-5,6-dicyano-1,4-benzoquinone / dioxane / 1 h / Heating 7: K2CO3 / methanol; tetrahydrofuran / 0.5 h / 0 °C View Scheme

Multi-step reaction with 2 steps 1: p-toluenesulfonic acid / 15 h / Heating2: 1.) Mg, ethylene dibromide, 2.) B2H6, 3.) aq. NaOH, H2O2  

Multi-step reaction with 5 steps 1: p-toluenesulfonic acid / 15 h / Heating2: 1.) Mg, ethylene dibromide, 2.) B2H6, 3.) aq. NaOH, H2O2 3: NaBH4 / ethanol / 0.5 h4: p-toluenesulfonic acid / benzene / 1 h / Heating5: pyridine / 3 h  

Multi-step reaction with 3 steps 1: p-toluenesulfonic acid / 15 h / Heating2: 1.) Mg, ethylene dibromide, 2.) B2H6, 3.) aq. NaOH, H2O2 3: NaBH4 / ethanol / 0.5 h