text: The major industrial synthesis involves the reaction of sulfur trioxide and sulfur dichloride: This synthesis can be adapted to the laboratory by heating oleum to slowly distill the sulfur trioxide into a cooled flask of sulfur dichloride.
  Other methods include syntheses from: 
  *Phosphorus pentachloride:
  *Chlorine and sulfur dichloride:
  *Phosgene:
  The second of the above four reactions also affords phosphorus oxychloride (phosphoryl chloride), which resembles thionyl chloride in many of its reactions.