1: 1,4-dibromo-2,5-di-n-octylbenzene With n-butyllithium in tetrahydrofuran; hexane T=-60°C; 0.25 h; 2: N,N-dimethyl-formamide in tetrahydrofuran; hexane T=-60 - 20°C; 1 h;

1.1: p-toluenesulfonic acid / benzene / 5 h / Heating 2.1: n-butyllithium / tetrahydrofuran; hexane / 0.17 h / -70 °C 2.2: tetrahydrofuran; hexane / -70 - 20 °C 3.1: p-toluenesulfonic acid / benzene / 2 h / Heating 4.1: 91 percent / trifluoroacetic acid / H2O / Heating View Scheme

1.1: p-toluenesulfonic acid / benzene / 5 h / Heating 2.1: n-butyllithium / tetrahydrofuran; hexane / 0.17 h / -70 °C 2.2: tetrahydrofuran; hexane / -70 - 20 °C 3.1: p-toluenesulfonic acid / benzene / 2 h / Heating View Scheme