Membered rings - IN - pyridines

PADP (171), an explosive synthesized from the reaction of 3,5-dinitro-2,6-bis-(hydrazino)pyridine with picryl chloride in DMF followed by oxidation with nitric acid, also exhibits high thermal stability. 2,4,6-Tris(picrylamino)-3,5-dinitropyridine (172) exhibits much lower thermal stability than both PYX (170) and PADP (171), a consequence of increased steric crowding around the pyridine ring. °  

The direct nitration of 2,6-diaminopyridine (168) with mixed acid yields 2,6-diamino-3,5-dinitropyridine (ANPy) (173). Oxidation of ANPy (173) with peroxyacetic acid yields ANPyO (174) (calculated VOD 7840 m/s, d = 1.88 g/crc ) C-Amination of ANPyO (174) with hydroxylamine hydrochloride in aqueous base yields the triamine (175), an impact insensitive explosive of high thermal stability.  

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