1: 1,2,3,4-tetramethylcyclopentadiene With n-butyllithium in diethyl ether; hexane 2: dimethyl-dichlorosilane in tetrahydrofuran

in tetrahydrofuran T=-30 - 20°C; Inert atmosphere;

1.1: lithium aluminium hydride / diethyl ether / 2 h 1.2: 37 percent / hydrochloric acid; air / diethyl ether; H2O / 16 h 2.1: n-butyllithium / petroleum ether / 16 h / 0 - 20 °C 2.2: 67 percent / petroleum ether; tetrahydrofuran / 16 h View Scheme

in tetrahydrofuran 16 h;

in pentane T=0°C; 12 h;