1: (1-Benzenesulfonyl-3-methyl-but-2-enyl)-trimethyl-silane With n-butyllithium in tetrahydrofuran; hexane T=-78°C; Metallation; 0.5 h; 2: benzaldehyde in tetrahydrofuran; hexane T=-78 - 0°C; Addition; Peterson elimination; 2 h;

1.1: BuLi / tetrahydrofuran; hexane / 0.5 h / -78 °C 1.2: tetrahydrofuran; hexane / 0.5 h / -78 - 20 °C 2.1: BuLi / tetrahydrofuran; hexane / 0.5 h / -78 °C 2.2: tetrahydrofuran; hexane / 2 h / -78 - 0 °C View Scheme

1.1: dimethylformamide 2.1: BuLi / tetrahydrofuran; hexane / 0.5 h / -78 °C 2.2: tetrahydrofuran; hexane / 0.5 h / -78 - 20 °C 3.1: BuLi / tetrahydrofuran; hexane / 0.5 h / -78 °C 3.2: tetrahydrofuran; hexane / 2 h / -78 - 0 °C View Scheme

1.1: dimethylformamide 2.1: BuLi / tetrahydrofuran; hexane / 0.5 h / -78 °C 2.2: tetrahydrofuran; hexane / 0.5 h / -78 - 20 °C 3.1: BuLi / tetrahydrofuran; hexane / 0.5 h / -78 °C 3.2: tetrahydrofuran; hexane / 2 h / -78 - 0 °C View Scheme

lithium hexamethyldisilazane in tetrahydrofuran; hexane Elimination; 3 h;