Styphnic acid

Styphnic acid
Names
IUPAC name
2,4,6-trinitrobenzene-1,3-diol
Identifiers
82-71-3 
ChemSpider 6465 Yes
Jmol-3D images Image
PubChem 6721
UN number 0219 – Dry or wetted with < 20% water/alcohol
0394 – Wetted with >= 20% water/alcohol
Properties
C6H3N3O8
Molar mass 245.11 g/mol
Density 1.829 g/cm3
Melting point 180 °C (356 °F; 453 K)
Boiling point decomposes
Except where noted otherwise, data is given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
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Infobox references

Styphnic acid, or 2,4,6-trinitro-1,3-benzenediol, is a yellow astringent acid that forms hexagonal crystals. It is used in the manufacture of dyes, pigments, inks, medicines, and explosives such as lead styphnate. It is itself a low sensitivity explosive, similar to picric acid, but explodes upon rapid heating.[1]

Preparation and chemistry

It may be prepared by the nitration of resorcinol with a mixture of nitric and sulfuric acid.[2]

This compound is an example of a trinitrophenol.

Like picric acid, it is a moderately strong acid, capable of displacing carbon dioxide from solutions of sodium carbonate, for example.

It may be reacted with weakly basic oxides, such as those of lead and silver, to form the corresponding salts.

The solubility of picric acid and styphnic acid in water is less than their corresponding mono- and di-nitro compounds, and far less than their non-nitrated percursor phenols, so they may be purified by fractional crystallisation.

References

  1. Synthesis of styphnic acid