sulfur in toluene 2 h;

1: 94 percent / dimethylformamide / 4 h / Heating 2: 92 percent / 20percent aqueous sodium hydroxide / 1 h / Heating 3: sulphur / toluene / 2 h View Scheme

1: 92 percent / 20percent aqueous sodium hydroxide / 1 h / Heating 2: sulphur / toluene / 2 h View Scheme

1: 66 percent / toluene / 5 h / Heating 2: 94 percent / dimethylformamide / 4 h / Heating 3: 92 percent / 20percent aqueous sodium hydroxide / 1 h / Heating 4: sulphur / toluene / 2 h View Scheme