sodium hydride in tetrahydrofuran 0 deg C, 1 h, then RT;

1: 90 percent / POCl3 / 4.5 h / 20 - 60 °C 2: NaH / tetrahydrofuran / 0 - 20 °C View Scheme

1: 1.) Na2CO3; 2.) KOH / 1.) acetic anhydride, 90 deg C, 45 min; 2.) reflux, 4 h 2: 85 percent / aq. HCl / 0.08 h / 80 °C 3: 90 percent / PCl5, POCl3 / 3 h / 100 °C 4: 1.) aq. HI, red P, KI; 2.) H2SO4 / 1.) 180 deg C, 7 h, high pressure; 2.) reflux, 3 h View Scheme

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