1: 98 percent / POCl3 / 6 h / 100 °C 2: 92 percent / N2H4 / ethanol / 2 h / Heating 3: 94 percent / N-methylpyrrolidone / 6 h / 160 °C 4: 1.) Me3SnN3, 2.) HCl (gas) / 1.) xylene, 115 deg C, 48 h, 2.) THF, RT, 1 h View Scheme