ammonium formate; palladium on activated charcoal in methanol T=25°C; 20 h;

sodium hydroxide; iodine; potassium iodide in 1,4-dioxane 2 h; cooling;

sodium chlorite; sodium dihydrogenphosphate; aminosulfonic acid; sodium sulfite in 1,4-dioxane 0.25 h;

1.1: 83 percent / N-ethyldiisopropylamine / CH2Cl2 / 2 h / 25 °C 2.1: sec-BuLi / tetrahydrofuran; cyclohexane / 2 h / -75 °C 2.2: 82 percent / 1,1,2-trichloro-1,2,2-trifluoroethane / tetrahydrofuran; cyclohexane / 1 h / -75 °C 3.1: BuLi / CH2Cl2; hexane / 6 h / -75 °C 3.2: CH2Cl2; hexane 3.3: 61 percent / aq. HCl / pH 1 4.1: 94 percent / ammonium formate / Pd/C / methanol / 20 h / 25 °C View Scheme

1.1: sec-BuLi / tetrahydrofuran; cyclohexane / 2 h / -75 °C 1.2: 82 percent / 1,1,2-trichloro-1,2,2-trifluoroethane / tetrahydrofuran; cyclohexane / 1 h / -75 °C 2.1: BuLi / CH2Cl2; hexane / 6 h / -75 °C 2.2: CH2Cl2; hexane 2.3: 61 percent / aq. HCl / pH 1 3.1: 94 percent / ammonium formate / Pd/C / methanol / 20 h / 25 °C View Scheme

1.1: BuLi / CH2Cl2; hexane / 6 h / -75 °C 1.2: CH2Cl2; hexane 1.3: 61 percent / aq. HCl / pH 1 2.1: 94 percent / ammonium formate / Pd/C / methanol / 20 h / 25 °C View Scheme

1: potassium carbonate / N,N-dimethyl-formamide / 20 h / 80 °C 2: sodium hydroxide / ethanol / 18 h / 40 °C View Scheme