hydrogenchloride; ammonia; sodium chloride in methanol

sodium disulfite; acetic acid in water T=90 - 92°C; 6 h; Yields of byproduct given;

hydrogen; potassium carbonate; triethylamine; palladium on activated charcoal in methanol 6 h; Ambient temperature;

potassium tert-butylate T=20°C; 2 h;

1: 83 percent / tetrahydrofuran / 12 h / 20 °C 2: 83 percent / 1,4-bis(methylamino)pyridine, DCC / CH2Cl2 / 18 h / 20 °C 3: 79 percent / NaH / tetrahydrofuran / 4 h / 20 °C 4: 79 percent / LiBr, H2O / dimethylformamide / 12 h / Heating 5: p-TsOH / toluene / 12 h / Heating 6: 1.) hydroquinone, 2.) 20percent AcOH / 1.) THF, 60 deg C, 2 d,2.) H2O, THF, 40 deg C, 72 h 7: 76 percent / LiOH, 30percent H2O2 / methanol / 5 h / 20 °C 8: 1.) NH2NH2*H2O, 2.) KOH, 3.) conc. HCl / 1.) diethylene glycol, 160 deg C, 1 h, 2.) 220-225 deg C, 4 h, 3.) H2O, 0 deg C, 4.) Et2O, 0 deg C 9: 1.) POCl3, 2.) 1M LiClO4, 3.) H2, 4.) 30percent ammonia / 3.) 10percent Pd/C / 1.) CH3CN, 100 deg C, 4 h, 2.) CH2Cl2, 10 min, 3.) DMF, 1 bar, 5 h 10: 70 percent / sodium bis(trimethylsilyl)amide / toluene; tetrahydrofuran / 2 h / 20 °C 11: 65 percent / tert-butyl nitrite, sodium bis(trimethylsilyl)amide / toluene; tetrahydrofuran / 1.5 h / 50 °C 12: p-TsOH, paraformaldehyde / acetic acid / 5 h / 100 - 105 °C 13: 40 percent / t-BuOK / 2 h / 20 °C View Scheme

1: 83 percent / 1,4-bis(methylamino)pyridine, DCC / CH2Cl2 / 18 h / 20 °C 2: 79 percent / NaH / tetrahydrofuran / 4 h / 20 °C 3: 79 percent / LiBr, H2O / dimethylformamide / 12 h / Heating 4: p-TsOH / toluene / 12 h / Heating 5: 1.) hydroquinone, 2.) 20percent AcOH / 1.) THF, 60 deg C, 2 d,2.) H2O, THF, 40 deg C, 72 h 6: 76 percent / LiOH, 30percent H2O2 / methanol / 5 h / 20 °C 7: 1.) NH2NH2*H2O, 2.) KOH, 3.) conc. HCl / 1.) diethylene glycol, 160 deg C, 1 h, 2.) 220-225 deg C, 4 h, 3.) H2O, 0 deg C, 4.) Et2O, 0 deg C 8: 1.) POCl3, 2.) 1M LiClO4, 3.) H2, 4.) 30percent ammonia / 3.) 10percent Pd/C / 1.) CH3CN, 100 deg C, 4 h, 2.) CH2Cl2, 10 min, 3.) DMF, 1 bar, 5 h 9: 70 percent / sodium bis(trimethylsilyl)amide / toluene; tetrahydrofuran / 2 h / 20 °C 10: 65 percent / tert-butyl nitrite, sodium bis(trimethylsilyl)amide / toluene; tetrahydrofuran / 1.5 h / 50 °C 11: p-TsOH, paraformaldehyde / acetic acid / 5 h / 100 - 105 °C 12: 40 percent / t-BuOK / 2 h / 20 °C View Scheme

1: p-TsOH / toluene / 12 h / Heating 2: 1.) hydroquinone, 2.) 20percent AcOH / 1.) THF, 60 deg C, 2 d,2.) H2O, THF, 40 deg C, 72 h 3: 76 percent / LiOH, 30percent H2O2 / methanol / 5 h / 20 °C 4: 1.) NH2NH2*H2O, 2.) KOH, 3.) conc. HCl / 1.) diethylene glycol, 160 deg C, 1 h, 2.) 220-225 deg C, 4 h, 3.) H2O, 0 deg C, 4.) Et2O, 0 deg C 5: 1.) POCl3, 2.) 1M LiClO4, 3.) H2, 4.) 30percent ammonia / 3.) 10percent Pd/C / 1.) CH3CN, 100 deg C, 4 h, 2.) CH2Cl2, 10 min, 3.) DMF, 1 bar, 5 h 6: 70 percent / sodium bis(trimethylsilyl)amide / toluene; tetrahydrofuran / 2 h / 20 °C 7: 65 percent / tert-butyl nitrite, sodium bis(trimethylsilyl)amide / toluene; tetrahydrofuran / 1.5 h / 50 °C 8: p-TsOH, paraformaldehyde / acetic acid / 5 h / 100 - 105 °C 9: 40 percent / t-BuOK / 2 h / 20 °C View Scheme

1: 1.) NH2NH2*H2O, 2.) KOH, 3.) conc. HCl / 1.) diethylene glycol, 160 deg C, 1 h, 2.) 220-225 deg C, 4 h, 3.) H2O, 0 deg C, 4.) Et2O, 0 deg C 2: 1.) POCl3, 2.) 1M LiClO4, 3.) H2, 4.) 30percent ammonia / 3.) 10percent Pd/C / 1.) CH3CN, 100 deg C, 4 h, 2.) CH2Cl2, 10 min, 3.) DMF, 1 bar, 5 h 3: 70 percent / sodium bis(trimethylsilyl)amide / toluene; tetrahydrofuran / 2 h / 20 °C 4: 65 percent / tert-butyl nitrite, sodium bis(trimethylsilyl)amide / toluene; tetrahydrofuran / 1.5 h / 50 °C 5: p-TsOH, paraformaldehyde / acetic acid / 5 h / 100 - 105 °C 6: 40 percent / t-BuOK / 2 h / 20 °C View Scheme

1: 79 percent / LiBr, H2O / dimethylformamide / 12 h / Heating 2: p-TsOH / toluene / 12 h / Heating 3: 1.) hydroquinone, 2.) 20percent AcOH / 1.) THF, 60 deg C, 2 d,2.) H2O, THF, 40 deg C, 72 h 4: 76 percent / LiOH, 30percent H2O2 / methanol / 5 h / 20 °C 5: 1.) NH2NH2*H2O, 2.) KOH, 3.) conc. HCl / 1.) diethylene glycol, 160 deg C, 1 h, 2.) 220-225 deg C, 4 h, 3.) H2O, 0 deg C, 4.) Et2O, 0 deg C 6: 1.) POCl3, 2.) 1M LiClO4, 3.) H2, 4.) 30percent ammonia / 3.) 10percent Pd/C / 1.) CH3CN, 100 deg C, 4 h, 2.) CH2Cl2, 10 min, 3.) DMF, 1 bar, 5 h 7: 70 percent / sodium bis(trimethylsilyl)amide / toluene; tetrahydrofuran / 2 h / 20 °C 8: 65 percent / tert-butyl nitrite, sodium bis(trimethylsilyl)amide / toluene; tetrahydrofuran / 1.5 h / 50 °C 9: p-TsOH, paraformaldehyde / acetic acid / 5 h / 100 - 105 °C 10: 40 percent / t-BuOK / 2 h / 20 °C View Scheme

1: 1.) hydroquinone, 2.) 20percent AcOH / 1.) THF, 60 deg C, 2 d,2.) H2O, THF, 40 deg C, 72 h 2: 76 percent / LiOH, 30percent H2O2 / methanol / 5 h / 20 °C 3: 1.) NH2NH2*H2O, 2.) KOH, 3.) conc. HCl / 1.) diethylene glycol, 160 deg C, 1 h, 2.) 220-225 deg C, 4 h, 3.) H2O, 0 deg C, 4.) Et2O, 0 deg C 4: 1.) POCl3, 2.) 1M LiClO4, 3.) H2, 4.) 30percent ammonia / 3.) 10percent Pd/C / 1.) CH3CN, 100 deg C, 4 h, 2.) CH2Cl2, 10 min, 3.) DMF, 1 bar, 5 h 5: 70 percent / sodium bis(trimethylsilyl)amide / toluene; tetrahydrofuran / 2 h / 20 °C 6: 65 percent / tert-butyl nitrite, sodium bis(trimethylsilyl)amide / toluene; tetrahydrofuran / 1.5 h / 50 °C 7: p-TsOH, paraformaldehyde / acetic acid / 5 h / 100 - 105 °C 8: 40 percent / t-BuOK / 2 h / 20 °C View Scheme