Trinitroresorcinol styphnic acid

Trinitroresorcinol (m. p. 175.5°C), also known as styphnic acid, is a yellow crystalline product which dyes animal fibres intensely. 100 ml of water dissolves 0.641 g of it at 14°C, and 1.136 g at 62°C. 

Knox and Richards [30] determined the solubility of styphnic acid in nitric acid of various concentrations at 25°C, expressed as the normality of the HN03 solutions. Aubertein and Emeury have recalculated their results expressing the solubility in a more convenient way  

Aubertein and Emeury have also determined the solubility of styphnic acid in sulphuric acid of different concentrations at 25°C  

The solubility of styphnic acid in nitric acid-sulphuric acid mixtures is very low. 

Aubertein and Emeury examined the solubility in a spent acid mixture of the composition  

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The reaction conditions necessary to obtain a good yield of the title compound (a difficult isomer), and to avoid hazards during the nitration of resorcinol, are critical and strict adherence to those specified is essential. The necessary 80% white fuming nitric acid must be completely free from oxides of nitrogen and nitrous acid, and procedures for this are detailed. Then the temperature dining addition of the diacetate must be kept between -10 and 0°C by regulating the rate of addition. The alternative use of 80% sulfuric acid as solvent for the 80% nitric acid (5 equiv.) is preferred as more reliable, but both methods have led to violent exothermic decomposition, accompanied by fume-off, after an induction period. In any event, the explosive 2,4,6-trinitroresorcinol ( styphnic acid ) is produced as a by-product. 

Dinitro-p-cresol 2,4,6-rTrinitroaniline (Picramide) sym-Trinitromesytylene (1,3,5-Triraethyl-2,4,6-trinitrobenzene) 2,4,6-Trinitroresorcinol (Styphnic Acid) 2-Amino-... 

Styphnates. Aromatic hydrocarbons (and also some amines and heterocyclic bases) form 1 1-addition products with styphnic acid (2 4 6-trinitroresorcinol),... 

Trinitroresorcinol (5) (styphnic acid) has also seen limited use as an explosive because of its acidic properties and the relatively high cost of resorcinol. However, the lead salt of styphnic acid has found use as a primary explosive in detonators and primers. 

The sulfonation-nitration strategy also provides a route to styphnic acid (5) (2,4,6-trinitroresorcinol) from resorcinol (22) but the control of temperature in this reaction is very important. The synthesis of styphnic acid (5) from the nitration of 2,4-dinitroresorcinol (24) with mixed acid or concentrated nitric acid is a higher yielding route. 2,4-Dinitroresorcinol (24) is conveniently prepared from the nitrosation of resorcinol (22) followed by oxidation of the resulting 2,4-dinitrosoresorcinol (23) with dilute nitric acid. 2,4-Dinitrosoresorcinol (23) also generates styphnic acid (5) on treatment with concentrated nitric acid. ... 

Trinitroresorcinol or Styphnic acid, dry or wetted with less than 20 per cent water, or mixtute of alcohol and water, by mass 0219... 

The presence of nitro groups in phenol and resorcinol enhances their acidic properties and that is why trinitrophenol is commonly known as picric acid while trinitroresorcinol is known as styphnic acid. 

Trinitro-1,3-dihydroxy benzene 2,4,6-Trinitroresorcinol or STYPHNIC ACID... 

The presence of nitro groups enhances the acidic properties of the phenol group. This is why the trinitro derivatives are also called acids, e.g. trinitrophenol is known as picric acid and trinitroresorcinol as styphnic acid. These compounds readily form salts with metals or bases. Polynitro derivatives of phenols also form addition compounds with hydrocarbons, e.g. naphthalene. 

Also called styphnic acid, trinitroresorcinol (Figure 3.16) is similar to picric acid except it has two hydroxyl groups. It is made in a similar manner to several... 

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