1: 1.75 M butyllithium / tetrahydrofuran; cyclohexane / -60 deg C; rt, 20 h; 37 deg C, 0.75 h 2: tetrahydrofuran View Scheme

n-butyllithium 1) THF, hexane, room temp., 23 h; 2) room temp., 15 h; Multistep reaction;

in tetrahydrofuran Yield given;

1: 1) n-BuLi / 1) THF, hexane, 0 deg C to room temp., 4 h; 2.) room temp., 12 h 2: 78 percent / TiCl3, K / tetrahydrofuran / THF, reflux, 15 h View Scheme

chloroform; thallium ethylate T=20°C; 22 h;

1: 99 percent / potassium hydrogen sulfate / 120 °C 2: naphthalenelithium / tetrahydrofuran / 0.08 h / -70 °C 3: dimethyl sulfate, sodium hydroxide; 20 percent sulfuric acid / H2O; toluene / 2 h / Ambient temperature 4: p-toluenesulfonic acid / benzene / 20 h / Heating View Scheme