Dinitrogen pentoxide amines

The tri-nitration of 1,3-dimethoxybenzene with mixed acid, followed by amination, is a patented route to DATB. A similar route to TATB employing 1,3,5-trimethoxybenzene and dinitrogen pentoxide only results in moderate yields. ... 

The first use of dinitrogen pentoxide as an A-nitrating agent appears to have been for the conversion of aromatic amines to arylnitramines. Difficulties in preparing pure dinitrogen pentoxide meant that reactions with aliphatic amines were not properly examined for another 60 years. 

Emmons and co-workers prepared a series of aliphatic secondary nitramines by treating amines with a solution of dinitrogen pentoxide in carbon tetrachloride at —30 C (Equation 5.9). The amine component needs to be in excess of two equivalents relative to the dinitrogen pentoxide if high yields of nitramine are to be attained. This is wasteful because at least half the amine remains unreacted. However, yields are high and there is no reason why the amine cannot be recovered as the nitrate salt. The method is particularly useful for the nitration of hindered secondary amines substrates such as those with branching on the a carbon. 

The reaction of dinitrogen pentoxide with primary aliphatic nitramines and amines leads to deamination and the formation of a nitrate ester as the major product. Consequently, dinitrogen pentoxide cannot be used for the synthesis of primary nitramines. In contrast, both primary and secondary arylamines undergo efficient A-nitration with dinitrogen pentoxide in chlorinated solvents. ... 

A solution of dinitrogen pentoxide in methylene chloride-acetonitrile also yields secondary nitramines from symmetrical methylenediamines. When the substiment is aliphatic or heterocyclic the nitrolysis occurs specifically at the aminal methylene and yields of secondary nitramine between 25 % and 54 % are reported. 

The nitrolysis of fert-butyl substituted amines with dinitrogen pentoxide in nitric acid solves many of these problems. However, these substrates are not always accessible via the usual condensation routes. The acidic reagents frequently used for these nitrolysis reactions are not always suitable for substrates with acid-sensitive or easily oxidized functionality. 

Solutions of dinitrogen pentoxide in aprotic solvents like methylene chloride, chloroform and carbon tetrachloride are efficient reagents for the iV-nitration of secondary amines. These reactions, known as nucleophilic nitrations , need excess amine present to react with the nitric acid formed during the reaction. Such nitrations are useful for the synthesis of secondary... 

Direct N-nitration of secondary amines by nitric acid is possible only for weakly basic amines. The more basic amines can be nitrated under neutral conditions widi reagents such as dinitrogen pentoxide and nitronium tetrafluoroborate, but nitrosamines are significant by-products. The nitrate ester CF3CMe20N02 has been recommended as a nonacidic nitrating agent for secondary amines which avoids the problem of contamination of the products by A(-nitrosamines piperidine and pyrrolidine were nitrated in yields of 75% and 72%, respectively. Amides and imides are efficiendy N-nitrated using ammonium nitrate in trifluoroacetic anhydride. ... 

SULFURIC OXYCHLORIDE (7791-25-5) SOjClj Forms corrosive mixture with air (Fire Rating 0). Reacts exothermically with water or steam, producing heat and yielding sulfuric acid and HCl vapors. Reacts violently with bases, amines, amides, inorganic hydroxides alkahs, alkali metals, dimethyl sulfoxide, dinitrogen pentoxide, lead dioxide (explosive reaction) N-methylformamide, red phosphorus. Reacts,... 

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