tetraphosphorus decasulfide in pyridine raised from 20 deg C to 60 deg C in 0.5 h, then 3.5 h at 60 deg C;

1: pyridine / toluene / 1 h / Heating 2: 89 percent / NH4Cl, polyphosphoric acid / 12 h / 180 °C 3: P2S5 / pyridine / raised from 20 deg C to 60 deg C in 0.5 h, then 3.5 h at 60 deg C View Scheme

1: 89 percent / NH4Cl, polyphosphoric acid / 12 h / 180 °C 2: P2S5 / pyridine / raised from 20 deg C to 60 deg C in 0.5 h, then 3.5 h at 60 deg C View Scheme

1: pyridine / toluene / 1 h / Heating 2: 89 percent / NH4Cl, polyphosphoric acid / 12 h / 180 °C 3: P2S5 / pyridine / raised from 20 deg C to 60 deg C in 0.5 h, then 3.5 h at 60 deg C View Scheme