1: 81.5 percent / dimethylsulfoxide / 0.5 h / 140 °C 2: 68.5 percent / KOH / methanol; H2O / 0.5 h / Heating 3: 68.7 percent / pyridine / 72 h / Ambient temperature 4: 98.6 percent / NaH / dimethylformamide / 2 h / 80 °C 5: 88 percent / 1N HCl / dioxane / 1.5 h / 90 °C 6: 79 percent / phosphorus oxychloride, Et3N, pyridine / CHCl3 / Ambient temperature 7: 100 percent / H2 / PdO / methanol; H2O / 1 h / Ambient temperature View Scheme

in dimethyl sulfoxide T=140°C; 0.5 h;