potassium hydroxide; sodium carbonate 1.) acetic anhydride, 90 deg C, 45 min; 2.) reflux, 4 h; Yield given. Multistep reaction;

1: 85 percent / aq. HCl / 0.08 h / 80 °C 2: 90 percent / PCl5, POCl3 / 3 h / 100 °C 3: 1.) aq. HI, red P, KI; 2.) H2SO4 / 1.) 180 deg C, 7 h, high pressure; 2.) reflux, 3 h View Scheme