phosphorus; hydrogen iodide; acetic anhydride T=95°C; 5 h;

1: 91 percent / sodium hypobromite / dioxane / 20 h / 20 °C 2: 85 percent / phosphorus red; acetic anhydride; HI / 5 h / 95 °C View Scheme

1: 91 percent / KOH / acetone / 7 h / 20 °C 2: 91 percent / sodium hypobromite / dioxane / 20 h / 20 °C 3: 85 percent / phosphorus red; acetic anhydride; HI / 5 h / 95 °C View Scheme

1: 95 percent / p-toluenesulfonic acid, 4A molecular sieves / CH2Cl2 / 72 h / Heating 2: 1.) TMEDA, n-BuLi / 1.) Et2O, from -30 deg C to -5 deg C, 4 h, 2.) Et2O, RT, overnight 3: glacial acetic acid / 1 h / Heating View Scheme

acetic acid 1 h; Heating; Yield given;

1: 1.) TMEDA, n-BuLi / 1.) Et2O, from -30 deg C to -5 deg C, 4 h, 2.) Et2O, RT, overnight 2: glacial acetic acid / 1 h / Heating View Scheme