1: 1.) NaH / 1.) DMF, 55 deg C, 1 h, 2.) DMF, 30-40 deg C, 1 h 2: 1.) tetramethylethylenediamine (TMEDA), n-butyllithium, 3.) concd HCl 3: 5.3 g / toluene / 24 h / Heating 4: 95percent hydrazine hydrate / ethanol / 0.5 h / Heating 5: 0.5 h / 320 °C 6: p-TSA / methanol / 1 h / 110 °C 7: 2 N HCl (aqueous) / methanol / 0.5 h / Heating View Scheme

1: 1.) tetramethylethylenediamine (TMEDA), n-butyllithium, 3.) concd HCl 2: 5.3 g / toluene / 24 h / Heating 3: 95percent hydrazine hydrate / ethanol / 0.5 h / Heating 4: 0.5 h / 320 °C 5: p-TSA / methanol / 1 h / 110 °C 6: 2 N HCl (aqueous) / methanol / 0.5 h / Heating View Scheme

1: 5.3 g / toluene / 24 h / Heating 2: 95percent hydrazine hydrate / ethanol / 0.5 h / Heating 3: 0.5 h / 320 °C 4: p-TSA / methanol / 1 h / 110 °C 5: 2 N HCl (aqueous) / methanol / 0.5 h / Heating View Scheme

1: p-TSA / methanol / 1 h / 110 °C 2: 2 N HCl (aqueous) / methanol / 0.5 h / Heating View Scheme

1: 95percent hydrazine hydrate / ethanol / 0.5 h / Heating 2: 0.5 h / 320 °C 3: p-TSA / methanol / 1 h / 110 °C 4: 2 N HCl (aqueous) / methanol / 0.5 h / Heating View Scheme