hydrogenchloride in tetrahydrofuran 1 h;

1: pyridinium chlorochromate, sodium acetate / CH2Cl2 / 1.5 h 2: tetrahydrofuran; diethyl ether / -78 °C 3: 86 percent / pyridinium chlorochromate, sodium acetate / CH2Cl2 / 1.5 h 4: 52 percent / p-toluenesulfonic acid / 7 h / Heating 5: 1.) n-butyllithium / 1.) THF, hexane, -78 deg C 2.) THF, hexane, 0 deg C 6: 1.) n-butyllithium, HMPA / 1.)THF, hexane, -78 degC to 0 degC 2.) 45-50 degC, 2 h 7: 63 percent / 5percent HCl / tetrahydrofuran; H2O / 2 h / 50 °C View Scheme

1: 52 percent / p-toluenesulfonic acid / 7 h / Heating 2: 1.) n-butyllithium / 1.) THF, hexane, -78 deg C 2.) THF, hexane, 0 deg C 3: 1.) n-butyllithium, HMPA / 1.)THF, hexane, -78 degC to 0 degC 2.) 45-50 degC, 2 h 4: 63 percent / 5percent HCl / tetrahydrofuran; H2O / 2 h / 50 °C View Scheme

1: tetrahydrofuran; diethyl ether / -78 °C 2: 86 percent / pyridinium chlorochromate, sodium acetate / CH2Cl2 / 1.5 h 3: 52 percent / p-toluenesulfonic acid / 7 h / Heating 4: 1.) n-butyllithium / 1.) THF, hexane, -78 deg C 2.) THF, hexane, 0 deg C 5: 1.) n-butyllithium, HMPA / 1.)THF, hexane, -78 degC to 0 degC 2.) 45-50 degC, 2 h 6: 63 percent / 5percent HCl / tetrahydrofuran; H2O / 2 h / 50 °C View Scheme

1: 86 percent / pyridinium chlorochromate, sodium acetate / CH2Cl2 / 1.5 h 2: 52 percent / p-toluenesulfonic acid / 7 h / Heating 3: 1.) n-butyllithium / 1.) THF, hexane, -78 deg C 2.) THF, hexane, 0 deg C 4: 1.) n-butyllithium, HMPA / 1.)THF, hexane, -78 degC to 0 degC 2.) 45-50 degC, 2 h 5: 63 percent / 5percent HCl / tetrahydrofuran; H2O / 2 h / 50 °C View Scheme

1: 99 percent / pyridine / 1.) 0 degC, 15 min 2.) room temperature, 12 h 2: 68 percent / AlCl3 / CS2 / 0.5 h / Ambient temperature 3: 95 percent / PCl5 / POCl3 / 2 h / 45 - 50 °C 4: 92 percent / NaNH2 / tetrahydrofuran; hexamethylphosphoric acid triamide / 1.) -78 degC 2.) 50 degC, 2 h 5: 94 percent / P(C6H5)3*Br2, collidine / CH2Cl2 / 5 h / Ambient temperature 6: 1.) n-butyllithium, HMPA / 1.)THF, hexane, -78 degC to 0 degC 2.) 45-50 degC, 2 h 7: 63 percent / 5percent HCl / tetrahydrofuran; H2O / 2 h / 50 °C View Scheme

1: 68 percent / AlCl3 / CS2 / 0.5 h / Ambient temperature 2: 95 percent / PCl5 / POCl3 / 2 h / 45 - 50 °C 3: 92 percent / NaNH2 / tetrahydrofuran; hexamethylphosphoric acid triamide / 1.) -78 degC 2.) 50 degC, 2 h 4: 94 percent / P(C6H5)3*Br2, collidine / CH2Cl2 / 5 h / Ambient temperature 5: 1.) n-butyllithium, HMPA / 1.)THF, hexane, -78 degC to 0 degC 2.) 45-50 degC, 2 h 6: 63 percent / 5percent HCl / tetrahydrofuran; H2O / 2 h / 50 °C View Scheme

1: 94 percent / P(C6H5)3*Br2, collidine / CH2Cl2 / 5 h / Ambient temperature 2: 1.) n-butyllithium, HMPA / 1.)THF, hexane, -78 degC to 0 degC 2.) 45-50 degC, 2 h 3: 63 percent / 5percent HCl / tetrahydrofuran; H2O / 2 h / 50 °C View Scheme

1: 1.) n-butyllithium, HMPA / 1.)THF, hexane, -78 degC to 0 degC 2.) 45-50 degC, 2 h 2: 63 percent / 5percent HCl / tetrahydrofuran; H2O / 2 h / 50 °C View Scheme

1: 1.) n-butyllithium, HMPA / 1.)THF, hexane, -78 degC to 0 degC 2.) 45-50 degC, 2 h 2: 63 percent / 5percent HCl / tetrahydrofuran; H2O / 2 h / 50 °C View Scheme