Molecular Proportions M.P. Description

TNT: Substance

1:1 Aniline 83-H4° Long brilliant red needles.

1:1 Dimethylaniline Violet needles.

1:1 m-Toluidine 62-63° Light red needles.

1:1 or-Naphthylamine 141.5° Dark red needles.

1:1 0-Naphthylamine 113.5° Bright red prismatic needlee.

1 : 1 0-Acetnaphthalide 106° Yellow needles.

1:1 Benzyl-/3-naphthylamine 106.5° Brilliant crimson needles.

1:1 Dibenzyl-£-naphthylamine — 108° Deep brick-red needles.

2 : 1 Benzaldehydephenylhydrazone 84° Dark red needles.

1:1 2-Methylindole 110° Yellow needles.

3:2 Carbazole 160° Yellow needles.

1:1 Carbazole 140-200° Dark yellow needles.

explodes or inflames when heated to about 230°, but Dupre found that the addition of solid caustic potash to TNT at 160° caused immediate inflammation or explosion. A mixture of powdered solid caustic potash and powdered TNT inflames when heated, either slowly or rapidly, to 80°. A similar mixture with caustic soda inflames at 80° if heated rapidly, but may be heated to 200° without taking fire if the heating is slow. If a small fragment of solid caustic potash is added to melted TNT at 100°, it becomes coated with a layer of reaction product and nothing further happens. If a drop of alcohol, in which both TNT and KOH are soluble, is now added, the material inflames within a few seconds. Mixtures of TNT with potassium and sodium carbonate do not ignite when heated suddenly to 100°.

Since the methyl group of TNT is attached to a picryl group, we should expect it in some respects to resemble the methyl group of a ketone. Although acetone and other methyl ketones bromi-nate with great ease, TNT does not brominate and may even be recrystallized from bromine. The methyl group of TNT, however, behaves like the methyl group of acetone in certain condensation reactions. In the presence of sodium carbonate TNT condenses with p-nitrosodimethylaniline to form the diraethylaminoanilide of trinitrobenzaldehyde, from which trinitrobenzaldehyde and N,N-dimethyl-p-diaminobenzene are produced readily by acid hydrolysis. 151

NO, NHft

If a drop of piperidine is added to a pasty mixture of TNT and benzaldehyde, the heat of the reaction is sufficient to cause the material to take fire. The same substances in alcohol or benzene solution condense smoothly in the presence of piperidine to form trinitrostilbene.

Preparation of Trinitrostilbene. To 10 grams of TNT dissolved in 25 cc. of benzene in a 100-cc. round-bottom flask equipped with a reflux condenser, 6 cc. of benzaldehyde and 0.5 cc. of piperidine are added, and the mixture is refluxed on the water bath for half an hour. Thei material, while still hot, is poured into a beaker and allowed to cool and crystallize. The crystals, collected on a filter, are rinsed twice with alcohol and recrystallized from a mixture of 2 volumes of alcohol and 1 of benzene. Brilliant yellow glistening needles, m.p. 158°.

Trinitrotoluene, in addition to the usual reactions of a nitrated hydrocarbon with alkali to form dangerous explosive materials, has the property that its methyl group in the presence of alkali condenses with aldehydic substances in reactions which produce heat and which may cause fire. Aldehydic substances from the action of nitrating acid on wood are always present where TNT is being manufactured, and alkali of all kinds ought to be excluded rigorously from the premises.

Giua reports that TNT may be distilled in vacuum without the slightest trace of decomposition. It boils at 210-212° at 10-20

mm. When heated for some time at 180-200°, or when exposed to

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