Nitrophenols

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Nitrophenols are a family of nitrated phenols with the formula HOC6H4NO2. Three isomeric nitrophenols exist:

  • o-Nitrophenol (1-hydroxy-2-nitrobenzene; OH and NO2 groups are neighboring; CAS number: 88-75-5), a yellow crystalline solid (m.p. 46 °C).
  • m-Nitrophenol (1-hydroxy-3-nitrobenzene), a yellow solid (m.p. 97 °C) and precursor to the drug aminosalicylic acid.
  • p-Nitrophenol (1-hydroxy-4-nitrobenzene, CAS number: 100-02-7), yellow crystals (m.p. 114 °C). It is a precursor to the rice herbicide fluorodifen and the pesticide parathion.

The nitrophenols are produced industrially by the reaction of chlorides with sodium hydroxide at temperatures close to 200 C.[1]

The mononitrated phenols are often hydrogenated to the corresponding aminophenols that are also useful industrially.[1]

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[edit] Di- and trinitrophenols

2,4-Dinitrophenol (m.p. 83 °C) is a moderately strong acid (pKa = 4.89). 2,4,6-trinitrophenol is better known as picric acid, which has a well developed chemistry.

[edit] Safety

Nitrophenols are poisonous. Occasionally, nitrophenols contaminate the soil near former explosives or fabric factories and military plants, and current research is aimed at remediation.

[edit] References

  1. ^ a b Gerald Booth "Nitro Compounds, Aromatic" in "Ullmann's Encyclopedia of Industrial Chemistry" 2007; John Wiley & Sons: New York.

[edit] External links

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