Cyclic methylene nitramines

On synthesis of cyclonite from paraformaldehyde, ammonium nitrate and acetic acid (method 4), products with cyclic structure, chiefly cyclonite and octogen, may arise due to the polymerization of the transiently-formed, hypothetical methylene-nitramine (XXVIII) [67] ... 

In addition to the Ross-Schiessler process, utilising p-CH20 and AN, the synthesis of RDX/ HMX mixts has also been reported starting with other smail molecules (Ref 7), namely, methyl-amine nitrate methylene diamine dinitrate and nitramine (NH2N02) in combination with CH20. In these reactions, the intermediate formation of Hexamine or a cyclic analog, is not necessarily established... 

N-Nitration. RDX, 5, is a cyclic nitramine obtained by the nitration of hexamethylene tetramine (HMT) in the presence of an excess of concentrated nitric acid. RDX is formed by the nitration of the three outside nitrogen atoms of HMT with removal of the internal nitrogen and methylene (-CH2-) groups. RDX is produced along with ammonium nitrate (NH4NO3) and formaldehyde (HCHO) as by-products. However, another molecule of RDX can be produced by adding NH4NO3, HCHO, and acetic acid (Eqs. 12.8 and 12.9) [1]. 

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