water; potassium hydroxide in methanol T=25°C; 12 h;

1: With n-butyllithium in tetrahydrofuran; hexane T=-78°C; 0.75 h; 2: With carbon dioxide in tetrahydrofuran; hexane T=-78 - 20°C; 12 h; Further stages.;

1: With sodium hydroxide; water in tetrahydrofuran; methanol T=20°C; 0.333333 h; Inert atmosphere; 2: With hydrogenchloride in tetrahydrofuran; methanol; water Inert atmosphere;

1.1: lithium diisopropyl amide / tetrahydrofuran / -78 °C 1.2: 9 h / -78 - 20 °C 1.3: 50 °C / Inert atmosphere 2.1: water; potassium hydroxide / methanol / 12 h / 25 °C View Scheme