potassium hydroxide in 1,4-dioxane; methanol 1.5 h; Heating;

sodium hydroxide; sodium tetrahydroborate

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

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

1: 95 percent / 15percent KOH / methanol; dioxane / 1.5 h / Heating 2: 83 percent / benzene; diethyl ether / 1 h / 20 - 25 °C 3: 88 percent / Jones reagent / acetone / 0.33 h / 0 - 5 °C 4: 1.) 10percent aq. HClO4, dibromantin, 2.) 10percent NaOH / 1.) acetone, 20 min, 2.) MeOH, 0-5 deg C, 1.5 h 5: HF, pyridine / 1 h / -78 °C View Scheme

1: 83 percent / benzene; diethyl ether / 1 h / 20 - 25 °C 2: 88 percent / Jones reagent / acetone / 0.33 h / 0 - 5 °C 3: 1.) 10percent aq. HClO4, dibromantin, 2.) 10percent NaOH / 1.) acetone, 20 min, 2.) MeOH, 0-5 deg C, 1.5 h 4: HF, pyridine / 1 h / -78 °C View Scheme

1: 95 percent / 15percent KOH / methanol; dioxane / Heating 2: 83 percent / benzene; diethyl ether / 1 h / 20 - 25 °C 3: 88 percent / Jones reagent / acetone / 0.33 h / 0 - 5 °C 4: 1.) 10percent aq. HClO4, dibromantin, 2.) 10percent NaOH / 1.) acetone, 20 min, 2.) MeOH, 0-5 deg C, 1.5 h 5: HF, pyridine / 1 h / -78 °C View Scheme

pyridine; hydrogen fluoride T=-78°C; 1 h; Yield given;

1: 88 percent / Jones reagent / acetone / 0.33 h / 0 - 5 °C 2: 1.) 10percent aq. HClO4, dibromantin, 2.) 10percent NaOH / 1.) acetone, 20 min, 2.) MeOH, 0-5 deg C, 1.5 h 3: HF, pyridine / 1 h / -78 °C View Scheme