The procedure is based on that described by Ruff and Winterfield. Thus, 94 ml. of Br2 is slowly added to 119 g of S (recrystallized from CS2) in a dry 500-ml pressure flask capable of withstanding 20 atm of internal pressure. (If proper precautions are observed, a beer bottle can be used.) The mixture is heated for two hours on a steam bath. The dark-red liquid product is distilled at 0.1 mm. The first cut contains primarily unreacted Br2; the main fraction distilling between 46 and 48℃ is pure S2Br2, while crystalline S remains in the distillation flask.The yield averages 80%.
