title: 4,4'-Dichlorodiphenyl sulfone
text: # 4,4'-Dichlorodiphenyl sulfone
  
  4,4′-Dichlorodiphenyl sulfone (DCDPS) is an organic compound with the formula $(ClC_6H_4)_2SO_2.$ Classified as a sulfone, this white solid is most commonly used as a precursor to polymers that are rigid and temperature-resistant such as PES or Udel.
  
  ## Synthesis and reactions
  
  DCDPS is synthesized via sulfonation of chlorobenzene with sulfuric acid, often in the presence of various additives to optimize the formation of the 4,4′-isomer:
  
      $ClC_6H_5$ + $SO_3$ → $(ClC_6H_4)_2SO_2$ + $H_2O$
  
  It can also be produced by chlorination of diphenylsulfone.
  
  With chloride substituents activated toward substitution, DCDPS is useful in the production of polysulfones:
  
      n $(ClC_6H_4)_2SO_2$ + n NaO−X−ONa → $[(O−X−OC_6H_4)_2SO_2]_n$ + 2n NaCl
  