Dow process (phenol)

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The Dow process is a method of phenol production through the hydrolysis of chlorobenzene.

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Benzene can be easily converted to chlorobenzene by nucleophilic aromatic substitution via a benzyne intermediate. [1] It is treated with aqueous sodium hydroxide at 350 °C and 300 bar or molten sodium hydroxide at 350 °C to convert it to sodium phenoxide, which yields phenol upon acidification. [2] When 1-[14C]-1-chlorobenzene was subjected to aqueous NaOH at 395 °C, ipso substitution product 1-[14C]-phenol was formed in 54% yield, while cine substitution product 2-[14C]-phenol was formed in 43% yield, indicating that an elimination-addition (benzyne) mechanism is predominant, with perhaps a small amount of product from addition-elimination (SNAr).[ citation needed ]

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References

  1. Reusch, William (1999). "Nucleophilic Substitution, Elimination & Addition Reactions of Benzene Derivatives". Virtual Textbook of Organic Chemistry . Retrieved 2021-10-08.
  2. "Dow process | phenol | Britannica".