Reaction with unsymmetrical trinitrotoluenes

Another extensive paper on the reaction of unsymmetrical trinitrotoluenes with ammonia leading to aminodinitroioluenes was that by Nielsen. Coon and co-workers [55]. The main purpose of this work was to identify the major com-... 

Crude TNT contains isomers and nitrated phenolic compounds resulting from side reactions. The usual method of purification is to treat crude TNT with 4% sodium sulfite solution at pH 8-9, which converts the unsymmetrical trinitro compounds to sulfonic acid derivatives. These by-products are then removed by washing with an alkaline solution. Pure TNT is then washed with hot water, flaked and packed. It is important to remove the waste acid and unsymmetrical trinitrotoluenes together with any by-products of nitration as they will degrade the TNT, reduce its shelf life, increase its sensitivity and reduce its compatibility with metals and other materials. Trace amounts of unsymmetrical trinitrotoluenes and by-products will also lower the melting point of TNT. TNT can be further recrystallized from organic solvents or 62% nitric acid. 

The reaction occurs with more difficulty than the corresponding one with the unsymmetrical trinitrotoluenes and requires a higher temperature or more concentrated solutions of sodium sulphite. The reaction of sulphitation of dinitro-toluene may be used in practice for removing m-nitrotoluene derivatives from mixtures of dinitro-isomers. Thus the sulphitation of trinitrotoluene becomes unnecessary. 

Brady [137] found that a concentrated solution of sodium acetate acted on unsymmetrical trinitrotoluene in a way similar to the action of weak alkalis, giving the corresponding dinitrocresols. Under such conditions less ill-defined amorphous products were obtained than in the reaction with strong alkalis, where they were formed in great quantities. 

Sodium hydroxide gives the following colour reactions with the unsymmetrical isomers of trinitrotoluene (Table 79). 

The unsymmetrical isomers of trinitrotoluene also give specific reactions with sodium carbonate and with lead oxide. The former also affects the ignition temperatures of the isomers. The corresponding data are tabulated below, in Table 80 (after Brunswig [141]). 

As Muraour [103] found, the reaction of sodium sulphite was not confined to unsymmetrical trinitro derivatives of toluene, a- Trinitrotoluene also reacted with Na2S03 to form dinitrotoluene sulphonic acid, the difference lying in the fact that the reaction proceeds much more slowly than with unsymmetrical isomers. A 3% solution of Na2S03, acting for 1 hr, dissolves at room temperature about 1% of a- trinitrotoluene. 

SPECIFIC REACTIONS OF THE UNSYMMETRICAL ISOMERS OF TRINITROTOLUENE WITH... 

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