1: 84 percent / H2SO4 / benzene / 20 h / Heating 2: 79 percent / <CoCp(CO)2> / 2 h / 145 °C 3: CsF / ethanol / 87 h / Ambient temperature 4: 65 percent / KOH / ethanol; H2O / 5 h / Ambient temperature 5: 68 percent / Et3N, diphenoxyphosphorylazid / 24 h / Heating 6: 81 percent / 37percent HCl / ethanol; H2O / 2 h / Heating 7: 72 percent / NaNO2 / aq. HCl; H2O / 1 h / 90 - 95 °C View Scheme