1.1: dimethylformamide / 20 °C 2.1: n-BuLi 2.2: -78 - 20 °C 3.1: LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran 4.1: TBAF / tetrahydrofuran / 1 h 5.1: Cp2ZrCl2 / 1,2-dichloro-ethane; hexane 5.2: 83 percent / NiCl2(PPh3)2; n-BuLi / tetrahydrofuran; hexane View Scheme

N-chloro-succinimide; dimethylsulfide in dichloromethane T=-40 - 0°C; 2 h;

1.1: dimethylformamide / 20 °C 2.1: n-BuLi 2.2: -78 °C 3.1: TsOH / methanol 4.1: LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran 5.1: 81 percent / N-chlorosuccinimide; Me2S / CH2Cl2 / 1.5 h / 0 °C 6.1: dimethylformamide 7.1: 79 percent / n-BuLi 8.1: LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran 9.1: TBAF / tetrahydrofuran 10.1: Cp2ZrCl2 / 1,2-dichloro-ethane; hexane 10.2: 89 percent / NiCl2(PPh3)2; n-BuLi / tetrahydrofuran; hexane View Scheme

tris(tetra-n-butylammonium)hydrogen diphosphate in acetonitrile T=20°C; 2 h;

lithium biphenylide; BaI2 in tetrahydrofuran T=-78°C; Yield given. Yields of byproduct given;