sulfuric acid in 1,4-dioxane; water 1 h; Heating;

sulfuric acid Inert atmosphere;

sulfuric acid; hydrogen; palladium on activated charcoal in 1,4-dioxane; water T=40 - 50°C; 5 h;

1: 87 percent / H2, H2SO4 / 10percent Pd/C / dioxane; H2O / 5 h / 40 - 50 °C 2: 83.3 percent / HCl(g) / 0.5 h / Heating View Scheme

1: 81 percent / methanol; H2O / 120 h / 20 °C 2: 63 percent / H2 / Pd/C / methanol; aq. HCl View Scheme

hydrazine hydrate in acetic acid Cyclization; 3 h; Heating;

1: 87 percent / H2, H2SO4 / 10percent Pd/C / dioxane; H2O / 5 h / 40 - 50 °C 2: 83.3 percent / HCl(g) / 0.5 h / Heating 3: 86.4 percent / LiAlH4 / diethyl ether / 1 h / Ambient temperature View Scheme

1: 87 percent / H2, H2SO4 / 10percent Pd/C / dioxane; H2O / 5 h / 40 - 50 °C 2: 83.3 percent / HCl(g) / 0.5 h / Heating 3: 86.4 percent / LiAlH4 / diethyl ether / 1 h / Ambient temperature 4: 74 percent / 48percent HBr, conc.H2SO4 / H2O / 4 h / Heating 5: 1.) Mg, iodine / 1.) Et2O, RT, 30 min, 2.) Et2O, -5 deg C, 20 min View Scheme