1.1: n-butyllithium / tetrahydrofuran; hexane / 0.3 h / -90 °C / Inert atmosphere 1.2: 0.5 h / -90 °C / Inert atmosphere 1.3: -90 °C 2.1: sulfuric acid / tetrahydrofuran; hexane / 0.1 h / -90 °C / Inert atmosphere View Scheme

n-butyllithium 1.) -95/-100 deg C, THF, hexane, 20 min; 2.) THF, -95 deg C, 2 h; Yield given. Multistep reaction;

n-butyllithium 1) THF, hexane, -95 to -100 deg C, 30 min; 2) THF, -95 deg C, 2 - 3 h; Multistep reaction. Yields of byproduct given;

n-butyllithium 1) THF, hexane, -95 to -100 deg C, 30 min; 2) THF, -95 deg C, 2 - 3 h; Multistep reaction. Yields of byproduct given;