1: With tert.-butyl lithium in diethyl ether; pentane T=-78°C; 2: With 1,2-di-iodoethane in diethyl ether; hexane T=-78 - 20°C; 1 h;

n-butyllithium 1.) THF, hexane, -78 deg C, 10 min, 2.) -78 deg C, 10 min; Yield given. Multistep reaction;

1: 89.4 percent / 5.0 molpercent Pd(PPh3)4 / tetrahydrofuran / 3 h / Ambient temperature 2: 96.1 percent / tetrabutylammonium fluoride / tetrahydrofuran / 0.02 h / Ambient temperature 3: K3Fe(CN)6, KOH / benzene / 51 h / Ambient temperature View Scheme