1: 2,2'-dibromo-5,5'-dichlorobiphenyl With n-butyllithium in tetrahydrofuran; hexane T=-60°C; 4 h; 2: di-n-hexyldichlorosilane in tetrahydrofuran; hexane T=20°C;

1.1: NaNO2; aq. HCl; NH3 / NaHCO3 / 0.17 h / 0 - 5 °C 1.2: 60 percent / CuCl; aq. HCl 2.1: n-BuLi / tetrahydrofuran; hexane / 4 h / -60 °C 2.2: 60 percent / hexane; tetrahydrofuran / 20 °C View Scheme

1.1: 40 percent / HNO3; H2SO4 / CH2Cl2 / 1 h / 100 °C 2.1: Fe; aq. HCl / ethanol / 1 h / Heating 3.1: NaNO2; aq. HCl; NH3 / NaHCO3 / 0.17 h / 0 - 5 °C 3.2: 60 percent / CuCl; aq. HCl 4.1: n-BuLi / tetrahydrofuran; hexane / 4 h / -60 °C 4.2: 60 percent / hexane; tetrahydrofuran / 20 °C View Scheme

1.1: Fe; aq. HCl / ethanol / 1 h / Heating 2.1: NaNO2; aq. HCl; NH3 / NaHCO3 / 0.17 h / 0 - 5 °C 2.2: 60 percent / CuCl; aq. HCl 3.1: n-BuLi / tetrahydrofuran; hexane / 4 h / -60 °C 3.2: 60 percent / hexane; tetrahydrofuran / 20 °C View Scheme