1.1: POCl3 2.1: dimethylformamide / 20 °C 3.1: TsOH / methanol / 12 h / 20 °C 4.1: 65 percent / n-BuLi 5.1: 100 percent / LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran / 3 h / 0 °C 6.1: N-chlorosuccinimide; Me2S / CH2Cl2 / 2.5 h / 0 °C 7.1: n-BuLi 7.2: -78 - 20 °C 8.1: LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran 9.1: TBAF / tetrahydrofuran / 1 h 10.1: Cp2ZrCl2 / 1,2-dichloro-ethane; hexane 10.2: 83 percent / NiCl2(PPh3)2; n-BuLi / tetrahydrofuran; hexane View Scheme

1.1: POCl3 2.1: dimethylformamide / 20 °C 3.1: TsOH / methanol / 12 h / 20 °C 4.1: 65 percent / n-BuLi 5.1: 100 percent / LiBHEt3; Pd(dppp)Cl2 / tetrahydrofuran / 3 h / 0 °C 6.1: N-chlorosuccinimide; Me2S / CH2Cl2 / 2.5 h / 0 °C 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

1: With tris(tetra-n-butylammonium)hydrogen diphosphate in acetonitrile T=20°C; 2 h; 2: With DOWEX 50WX8-200; ammonium hydrogen carbonate in isopropyl alcohol pH=8.0; Further stages.;