toluene-4-sulfonic acid 12 h; Heating;

1: 95 percent / 5percent KOH / methanol / Heating 2: 85.7 percent / (NCOOEt)2, Ph3P / 1.) THF, 4 h, 2.) benzene, 0-5 deg C, 2 h 3: 84 percent / PhICl2 / CH2Cl2 / 0.75 h / 10 - 15 °C / Irradiation 4: 95 percent / 15percent KOH / methanol; dioxane / 1.5 h / Heating 5: 83 percent / benzene; diethyl ether / 1 h / 20 - 25 °C 6: 88 percent / Jones reagent / acetone / 0.33 h / 0 - 5 °C 7: 1.) 10percent aq. HClO4, dibromantin, 2.) 10percent NaOH / 1.) acetone, 20 min, 2.) MeOH, 0-5 deg C, 1.5 h 8: HF, pyridine / 1 h / -78 °C 9: 72 percent / 15percent KOH / methanol; dioxane / 1.5 h / Heating View Scheme

1: 95 percent / 5percent KOH / methanol / Heating 2: 85.7 percent / (NCOOEt)2, Ph3P / 1.) THF, 4 h, 2.) benzene, 0-5 deg C, 2 h 3: 84 percent / PhICl2 / CH2Cl2 / 0.75 h / 10 - 15 °C / Irradiation 4: 95 percent / 15percent KOH / methanol; dioxane / 1.5 h / Heating 5: 83 percent / benzene; diethyl ether / 1 h / 20 - 25 °C 6: 88 percent / Jones reagent / acetone / 0.33 h / 0 - 5 °C 7: 1.) 10percent aq. HClO4, dibromantin, 2.) 10percent NaOH / 1.) acetone, 20 min, 2.) MeOH, 0-5 deg C, 1.5 h 8: HF, pyridine / 1 h / -78 °C View Scheme