1: 99 percent / POCl3 / CHCl3 / 6 h / Heating 2: 95 percent / tetrahydrofuran / 3 h / Ambient temperature 3: 52 percent / cerium(IV) ammonium nitrate / acetonitrile; H2O / 0.5 h / 10 - 20 °C View Scheme

1: 99 percent / POCl3 / CHCl3 / 6 h / Heating 2: 96 percent / tetrahydrofuran / 3 h / Ambient temperature 3: 87 percent / p-toluenesulfonic acid monohydrate / acetone / 3 h / 0 - 5 °C 4: 86 percent / diethyl ether; tetrahydrofuran / 3 h / Ambient temperature View Scheme

1: 99 percent / POCl3 / CHCl3 / 6 h / Heating 2: 96 percent / tetrahydrofuran / 3 h / Ambient temperature 3: 87 percent / p-toluenesulfonic acid monohydrate / acetone / 3 h / 0 - 5 °C 4: 86 percent / diethyl ether; tetrahydrofuran / 3 h / Ambient temperature 5: 70 percent / cerium(IV) ammonium nitrate / CHCl3; acetonitrile; H2O / 0.17 h / Ambient temperature View Scheme

1: 99 percent / POCl3 / CHCl3 / 6 h / Heating 2: 96 percent / tetrahydrofuran / 3 h / Ambient temperature 3: 87 percent / p-toluenesulfonic acid monohydrate / acetone / 3 h / 0 - 5 °C 4: 86 percent / diethyl ether; tetrahydrofuran / 3 h / Ambient temperature 5: 70 percent / cerium(IV) ammonium nitrate / CHCl3; acetonitrile; H2O / 0.17 h / Ambient temperature 6: 27 percent / AgO, 40percent HNO3 / acetone / 0.17 h / Ambient temperature View Scheme

1: 99 percent / POCl3 / CHCl3 / 6 h / Heating 2: 96 percent / tetrahydrofuran / 3 h / Ambient temperature 3: 87 percent / p-toluenesulfonic acid monohydrate / acetone / 3 h / 0 - 5 °C View Scheme

1: 99 percent / POCl3 / CHCl3 / 6 h / Heating 2: 95 percent / tetrahydrofuran / 3 h / Ambient temperature 3: 52 percent / cerium(IV) ammonium nitrate / acetonitrile; H2O / 0.5 h / 10 - 20 °C 4: 26 percent / AlCl3 / CH2Cl2 / 1 h / Ambient temperature View Scheme