1: 12.2 g / BuLi / hexane; diethyl ether / 3 h / -50 °C 2: 24.3 g / p-toluenesulfonic acid / toluene / 6 h / Heating 3: 2.5 g / BuLi / diethyl ether; hexane / 4 h / -50 °C 4: 1.) NaH, 2.) conc. HCl / 1.) DME, 2 h, 2.) ethanol, H2O, steam bath, 10 min 5: 1.) BuLi, 2.) NaOH / 1.) hexane, toluene, 75 deg C, 2 h, 2.) ethanol, steam bath, 10 min View Scheme

1: 24.3 g / p-toluenesulfonic acid / toluene / 6 h / Heating 2: 2.5 g / BuLi / diethyl ether; hexane / 4 h / -50 °C 3: 1.) NaH, 2.) conc. HCl / 1.) DME, 2 h, 2.) ethanol, H2O, steam bath, 10 min 4: 1.) BuLi, 2.) NaOH / 1.) hexane, toluene, 75 deg C, 2 h, 2.) ethanol, steam bath, 10 min View Scheme

1: 2.5 g / BuLi / diethyl ether; hexane / 4 h / -50 °C 2: 1.) NaH, 2.) conc. HCl / 1.) DME, 2 h, 2.) ethanol, H2O, steam bath, 10 min 3: 1.) BuLi, 2.) NaOH / 1.) hexane, toluene, 75 deg C, 2 h, 2.) ethanol, steam bath, 10 min View Scheme

1: 1.) NaH, 2.) conc. HCl / 1.) DME, 2 h, 2.) ethanol, H2O, steam bath, 10 min 2: 1.) BuLi, 2.) NaOH / 1.) hexane, toluene, 75 deg C, 2 h, 2.) ethanol, steam bath, 10 min View Scheme

sodium hydroxide; n-butyllithium 1.) hexane, toluene, 75 deg C, 2 h, 2.) ethanol, steam bath, 10 min; Yield given. Multistep reaction. Yields of byproduct given;