1: 91 percent / benzene / 24 h / Heating 2: butyllithium, HMPA / hexane / 3.5 h / -65 °C 3: tetrahydrofuran / 1 h at -65 deg C, then 19 h at room temp. 4: 1) Na, liquid NH3; 2) TsOH monohydrate / 1) diethyl ether, -60 deg C, 5 min; 2) MeOH, room temp., 15 h View Scheme

Multi-step reaction with 2 steps 1: 91 percent / benzene / 24 h / Heating2: butyllithium, HMPA / hexane / 3.5 h / -65 °C  

Multi-step reaction with 3 steps 1: 91 percent / benzene / 24 h / Heating2: butyllithium, HMPA / hexane / 3.5 h / -65 °C3: tetrahydrofuran / 1 h at -65 deg C, then 19 h at room temp.