1: toluene / 24 h / 110 °C 2: toluene / 3 h / 20 °C 3: acetic acid; iron / 3 h / 90 °C 4: water; sodium hydroxide / methanol / 3 h / 20 °C View Scheme

sulfuric acid; water

hydrogenchloride in methanol; potassium carbonate; acetone

1: pyridine / toluene / 6 h / Heating 2: 53 percent / 80percent H2SO4 / 0.5 h / 75 °C 3: 94 percent / POCl3 / dimethylformamide / 3 h / 90 °C 4: 77 percent / CAN / H2O; acetonitrile / 0.25 h / 0 °C 5: 1.) conc. HCl, 2.) K2CO3, TDA-1 / 1.) CHCl3, 35 deg C, 8 h; 5 min, RT; 2.) DMF, 25 deg C, 1 h 6: 13 percent / H2 / 10percent palladium on carbon / pyridine; methanol / 20 h View Scheme

palladium 10 on activated carbon; hydrazine hydrate in ethanol T=23°C; 0.333333 h; Inert atmosphere;