1: With triphenylphosphine; bis(1,5-cyclooctadiene)nickel (0) in tetrahydrofuran T=0°C; 0.0833333 h; 2: With hydrogenchloride in tetrahydrofuran T=0°C; 1 h;

1.1: 71 percent / NaH / tetrahydrofuran 2.1: DIBAL-H 3.1: PPTS / CH2Cl2 4.1: PdCl2(PPh3)2 / dimethylformamide 5.1: TBAF / tetrahydrofuran 6.1: 81 percent / PCC; MS4A / CH2Cl2 7.1: PPh3 / Ni(cod)2 / tetrahydrofuran / 0.08 h / 0 °C 7.2: 67 percent / aq. HCl / tetrahydrofuran / 1 h / 0 °C View Scheme

1.1: 81 percent / PCC; MS4A / CH2Cl2 2.1: PPh3 / Ni(cod)2 / tetrahydrofuran / 0.08 h / 0 °C 2.2: 67 percent / aq. HCl / tetrahydrofuran / 1 h / 0 °C View Scheme

1.1: PdCl2(PPh3)2 / dimethylformamide 2.1: TBAF / tetrahydrofuran 3.1: 81 percent / PCC; MS4A / CH2Cl2 4.1: PPh3 / Ni(cod)2 / tetrahydrofuran / 0.08 h / 0 °C 4.2: 67 percent / aq. HCl / tetrahydrofuran / 1 h / 0 °C View Scheme