in pyridine 15 h; Heating;

1: 91 percent / NaOH / H2O / 2 h / Heating 2: 75 percent / pyridine / 15 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: 75 percent / pyridine / 15 h / Heating View Scheme

1: 1.) acetic anhydride / 1.) 0-50 deg C, 30 min, 2.) 25 deg C, 3.5 d 2: 90 percent / K2CO3 / dimethylformamide / 1.5 h / Ambient temperature 3: 91 percent / NaOH / H2O / 2 h / Heating 4: 75 percent / pyridine / 15 h / Heating View Scheme

1: 90 percent / K2CO3 / dimethylformamide / 1.5 h / Ambient temperature 2: 91 percent / NaOH / H2O / 2 h / Heating 3: 75 percent / pyridine / 15 h / Heating View Scheme

in dimethylsulfoxide-d6 T=120 - 130°C;

1: 84 percent / 80percent NaH / dioxane / 1. 10 min., room temp. 2. 2.5 h, reflux 2: 85 percent / KOH / H2O / 1 h / Heating 3: 72 percent / dimethylsulfoxide / 2.5 h / 140 °C View Scheme

1: 88 percent / ethanol / 1 h / Ambient temperature 2: 84 percent / 80percent NaH / dioxane / 1. 10 min., room temp. 2. 2.5 h, reflux 3: 85 percent / KOH / H2O / 1 h / Heating 4: 72 percent / dimethylsulfoxide / 2.5 h / 140 °C View Scheme