n-butyllithium in tetrahydrofuran T=-78 - 20°C;

1.1: NaOEt / H2O; dimethylformamide / 24 h / 20 °C 2.1: n-BuLi / hexane; tetrahydrofuran / -78 - 20 °C 2.2: 9 g / hexane; tetrahydrofuran / -78 - 20 °C View Scheme