1: 45 percent / 4 h / 100 °C 2: 1.) MsCl, Et3N, 2.) NaCl / 1.) 1,2-dichloroethane, 0 deg, 2.) DMF, 160 deg View Scheme

1: 98 percent / ethanol; H2O / 2 h / 100 °C 2: 1.) H2, HCOOH / 1.) 5percent Pd/C / 1.) C2H5OH, 20 deg C, 2.) reflux, 2 h 3: 59 percent / P2S5, pyridine / 16 h / Heating 4: 54 percent / KOH / methanol; H2O / 1 h / Ambient temperature View Scheme

ammonium hydroxide T=0°C; Substitution; 0.5 h;

1: SOCl2 / dimethylformamide / 4 h / Heating 2: conc. aq. NH4OH / 0.5 h / 0 °C View Scheme

1: 36 percent / conc. H2SO4; KNO3 / 1.08 h / 40 - 145 °C 2: SOCl2 / dimethylformamide / 4 h / Heating 3: conc. aq. NH4OH / 0.5 h / 0 °C View Scheme