ammonium formate; palladium on activated charcoal in tetrahydrofuran; methanol T=40°C; 4 h;

1.1: NaH / dimethylformamide / 20 °C 1.2: 75 percent / dimethylformamide / 20 °C 2.1: n-BuLi; iPr2NH / tetrahydrofuran / 1 h / -78 °C 2.2: tetrahydrofuran / -78 - 20 °C 2.3: 77 percent / 6N HCl / CH2Cl2 / 1 h / Heating 3.1: 100 percent / thionyl chloride / 1 h / Heating 4.1: n-Buli; iPr2NH / tetrahydrofuran / 0.5 h / 0 °C 4.2: tetrahydrofuran / -78 - 20 °C 5.1: 53 percent / TBAF / tetrahydrofuran; methanol / Heating 6.1: 65 percent / ammonium formate / Pd/C / methanol; tetrahydrofuran / 4 h / 40 °C View Scheme

1.1: n-BuLi; iPr2NH / tetrahydrofuran / 1 h / -78 °C 1.2: tetrahydrofuran / -78 - 20 °C 1.3: 77 percent / 6N HCl / CH2Cl2 / 1 h / Heating 2.1: 100 percent / thionyl chloride / 1 h / Heating 3.1: n-Buli; iPr2NH / tetrahydrofuran / 0.5 h / 0 °C 3.2: tetrahydrofuran / -78 - 20 °C 4.1: 53 percent / TBAF / tetrahydrofuran; methanol / Heating 5.1: 65 percent / ammonium formate / Pd/C / methanol; tetrahydrofuran / 4 h / 40 °C View Scheme

1.1: n-Buli; iPr2NH / tetrahydrofuran / 0.5 h / 0 °C 1.2: tetrahydrofuran / -78 - 20 °C 2.1: 53 percent / TBAF / tetrahydrofuran; methanol / Heating 3.1: 65 percent / ammonium formate / Pd/C / methanol; tetrahydrofuran / 4 h / 40 °C View Scheme

1.1: 100 percent / thionyl chloride / 1 h / Heating 2.1: n-Buli; iPr2NH / tetrahydrofuran / 0.5 h / 0 °C 2.2: tetrahydrofuran / -78 - 20 °C 3.1: 53 percent / TBAF / tetrahydrofuran; methanol / Heating 4.1: 65 percent / ammonium formate / Pd/C / methanol; tetrahydrofuran / 4 h / 40 °C View Scheme

1.1: n-Buli; iPr2NH / tetrahydrofuran / 0.5 h / 0 °C 1.2: tetrahydrofuran / -78 - 20 °C 2.1: 53 percent / TBAF / tetrahydrofuran; methanol / Heating 3.1: 65 percent / ammonium formate / Pd/C / methanol; tetrahydrofuran / 4 h / 40 °C View Scheme