1: 1.) Mg, EtBr / 1.) THF, 55 degC, 1 h; 2.) THF, romtemp., 1 h 2: 84 percent / H2SO4 / benzene / 20 h / Heating 3: 79 percent / <CoCp(CO)2> / 2 h / 145 °C 4: CsF / ethanol / 87 h / Ambient temperature 5: 65 percent / KOH / ethanol; H2O / 5 h / Ambient temperature 6: 68 percent / Et3N, diphenoxyphosphorylazid / 24 h / Heating 7: 81 percent / 37percent HCl / ethanol; H2O / 2 h / Heating 8: 72 percent / NaNO2 / aq. HCl; H2O / 1 h / 90 - 95 °C View Scheme

lithium hexamethyldisilazane in tetrahydrofuran T=-78°C; 2 h;

n-butyllithium 1.) THF-hexan, roomtemp., 2 h; 2.) THF-hexan, reflux, 4 h; Yield given. Multistep reaction;