sulfuric acid; sodium nitrite T=0°C; 0.5 h;

1: 75 percent / POCl3, pyridine / chlorobenzene / 1 h / Heating 2: 90 percent / Et3N / 144 h / Heating View Scheme

1: 75 percent / POCl3, pyridine / chlorobenzene / 1 h / Heating 2: 90 percent / Et3N / 144 h / Heating 3: 95 percent / H2 / 10percent Pd/C / ethanol / 760 Torr View Scheme

pyridine; trichlorophosphate in chlorobenzene 1 h; Heating;