1: 61 percent / K2CO3 / dimethylformamide / 15 h / 100 °C 2: NaOH , FeSO4 / 1) aq NaOH,reflux,4 h 2) reflux 30 min 3: 54 percent / Hydrogen fluoride, Sodium nitrite / pyridine / a) Dissolving in HF and pyridine at 0 deg C and then 30 min at room temperature b) Sodium nitrite was added at 0 deg C c) Then 30 min at 30 deg C and 3h at 70 deg C View Scheme

1: NaH / dimethylformamide / 5 h / Heating 2: aq. NaOH / 0.5 h / Heating 3: dimethylformamide / 8 h / 140 °C View Scheme

potassium carbonate in N,N-dimethyl-formamide T=95°C; 7 h; Inert atmosphere;

potassium carbonate T=190°C; 1.5 h; Yield given;

1: 78 percent / K2CO3, O-(2,4-dinitrophenyl)hydroxylamine / dimethylformamide / 3 h / Ambient temperature 2: 1.) acetic anhydride / 1.) 0-50 deg C, 30 min, 2.) 25 deg C, 3.5 d 3: 90 percent / K2CO3 / dimethylformamide / 1.5 h / Ambient temperature 4: 91 percent / NaOH / H2O / 2 h / Heating 5: 65 percent / pyridine / 15 h / Heating View Scheme

potassium carbonate; O-(2,4-dinitro-phenyl)-hydroxylamine in N,N-dimethyl-formamide 3 h; Ambient temperature;

1: 78 percent / K2CO3, O-(2,4-dinitrophenyl)hydroxylamine / dimethylformamide / 3 h / Ambient temperature 2: 1.) acetic anhydride / 1.) 0-50 deg C, 30 min, 2.) 25 deg C, 3.5 d View Scheme

1: 78 percent / K2CO3, O-(2,4-dinitrophenyl)hydroxylamine / dimethylformamide / 3 h / Ambient temperature 2: 1.) acetic anhydride / 1.) 0-50 deg C, 30 min, 2.) 25 deg C, 3.5 d 3: 90 percent / K2CO3 / dimethylformamide / 1.5 h / Ambient temperature View Scheme

1: 78 percent / K2CO3, O-(2,4-dinitrophenyl)hydroxylamine / dimethylformamide / 3 h / Ambient temperature 2: 1.) acetic anhydride / 1.) 0-50 deg C, 30 min, 2.) 25 deg C, 3.5 d 3: 90 percent / K2CO3 / dimethylformamide / 1.5 h / Ambient temperature 4: 91 percent / NaOH / H2O / 2 h / Heating View Scheme

1: 78 percent / K2CO3, O-(2,4-dinitrophenyl)hydroxylamine / dimethylformamide / 3 h / Ambient temperature 2: 1.) acetic anhydride / 1.) 0-50 deg C, 30 min, 2.) 25 deg C, 3.5 d 3: 90 percent / K2CO3 / dimethylformamide / 1.5 h / Ambient temperature 4: 91 percent / NaOH / H2O / 2 h / Heating 5: 65 percent / pyridine / 15 h / Heating 6: 82 percent / 1.) 0.1N NaOH, 30percent H2O2, 2.) 10percent Pd/C / 1.) 45 deg C, 20 h, 2.) 25 deg C, 1 h View Scheme