1: 2,3-Dichloropyrazine With Iron (III) nitrate nonahydrate; dipotassium peroxodisulfate; trifluoroacetic acid in water T=20°C; 0.166667 h; Schlenk technique; 2: 3,4,5-trimethoxyphenylboronic acid in water T=70°C; 24 h; Schlenk technique;

1: 4 h; Heating / reflux; 2: With sodium hydroxide in water

1: 34 percent / KOH / ethanol / 5 h / Heating 2: 76 percent / 90percent H2O2, maleic anhydride / CH2Cl2 / 1) r.t., overnight, 2) reflux, 2 h 3: 1 h / Heating 4: 10percent KOH / methanol / 1 h / Heating 5: POCl3, PCl5 / 1 h / 160 °C 6: 25 percent / 90percent H2O2, maleic anhydride / CHCl3 / 1) r.t., overnight, 2) reflux, 3 h 7: POCl3 / 0.5 h / Heating View Scheme

1: 76 percent / 90percent H2O2, maleic anhydride / CH2Cl2 / 1) r.t., overnight, 2) reflux, 2 h 2: 1 h / Heating 3: 10percent KOH / methanol / 1 h / Heating 4: POCl3, PCl5 / 1 h / 160 °C 5: 25 percent / 90percent H2O2, maleic anhydride / CHCl3 / 1) r.t., overnight, 2) reflux, 3 h 6: POCl3 / 0.5 h / Heating View Scheme

1: 1 h / Heating 2: 10percent KOH / methanol / 1 h / Heating 3: POCl3, PCl5 / 1 h / 160 °C 4: 25 percent / 90percent H2O2, maleic anhydride / CHCl3 / 1) r.t., overnight, 2) reflux, 3 h 5: POCl3 / 0.5 h / Heating View Scheme

1: 49 percent / 90percent H2O2, maleic anhydride / CHCl3 / 1) r.t., overnight, 2) reflux, 3 h 2: hydrazine hydrate / ethanol / 2 h / 140 °C 3: CuSO4*5H2O, / acetic acid; H2O / 1 h / Heating 4: 1 h / Heating 5: 10percent KOH / methanol / 1 h / Heating 6: POCl3, PCl5 / 1 h / 160 °C 7: 74 percent / 90percent H2O2, maleic anhydride / CHCl3 / 1) r.t., overnight, 2) reflux, 3 h 8: POCl3 / 0.5 h / Heating View Scheme

1: 10percent KOH / methanol / 1 h / Heating 2: POCl3, PCl5 / 1 h / 160 °C 3: 49 percent / 90percent H2O2, maleic anhydride / CHCl3 / 1) r.t., overnight, 2) reflux, 3 h 4: hydrazine hydrate / ethanol / 2 h / 140 °C 5: CuSO4*5H2O, / acetic acid; H2O / 1 h / Heating 6: 1 h / Heating 7: 10percent KOH / methanol / 1 h / Heating 8: POCl3, PCl5 / 1 h / 160 °C 9: 74 percent / 90percent H2O2, maleic anhydride / CHCl3 / 1) r.t., overnight, 2) reflux, 3 h 10: POCl3 / 0.5 h / Heating View Scheme

1: hydrazine hydrate / ethanol / 2 h / 140 °C 2: CuSO4*5H2O, / acetic acid; H2O / 1 h / Heating 3: 1 h / Heating 4: 10percent KOH / methanol / 1 h / Heating 5: POCl3, PCl5 / 1 h / 160 °C 6: 74 percent / 90percent H2O2, maleic anhydride / CHCl3 / 1) r.t., overnight, 2) reflux, 3 h 7: POCl3 / 0.5 h / Heating View Scheme

1: POCl3, PCl5 / 1 h / 160 °C 2: 49 percent / 90percent H2O2, maleic anhydride / CHCl3 / 1) r.t., overnight, 2) reflux, 3 h 3: hydrazine hydrate / ethanol / 2 h / 140 °C 4: CuSO4*5H2O, / acetic acid; H2O / 1 h / Heating 5: 1 h / Heating 6: 10percent KOH / methanol / 1 h / Heating 7: POCl3, PCl5 / 1 h / 160 °C 8: 74 percent / 90percent H2O2, maleic anhydride / CHCl3 / 1) r.t., overnight, 2) reflux, 3 h 9: POCl3 / 0.5 h / Heating View Scheme

1: 1 h / Heating 2: 10percent KOH / methanol / 1 h / Heating 3: POCl3, PCl5 / 1 h / 160 °C 4: 74 percent / 90percent H2O2, maleic anhydride / CHCl3 / 1) r.t., overnight, 2) reflux, 3 h 5: POCl3 / 0.5 h / Heating View Scheme