Aminonitropyridines and their <i>N</i>‐oxides

Abstract

Abstract 2,6‐Diamino‐3,5‐dinitropyridine 1‐oxide has been prepared by mixed acid nitration of 2,6‐diaminopyridine, followed by oxidation using hydrogen peroxide in acetic acid. 3,5‐Dinitro‐2,4,6‐triaminopyridine has been prepared by oxidative amination of 2‐chloro‐3,5‐dinitropyridine or 2,6‐diamino‐3,5‐dinitropyridine using potassium permanganate in liquid ammonia, or by “vicarious nucleophilic amination” of 2,6‐diarnino‐3,5‐dinitropyridine using hydroxylamine in aqueous potassium hydroxide. 3,5‐Dinitro‐2,4,6‐triaminopyridine 1‐oxide has been prepared by oxidation of 3,5‐dinitro‐2,4,6‐triaminopyridine using hydrogen peroxide in acetic acid, and by “vicarious nucleophilic amination” of 2,6‐diamino‐3,5‐dinitropyridine 1‐oxide. Nmr spectroscopy and single crystal X‐ray diffraction studies have shown that these compounds have the planar structures and intra‐ and inter‐molecular hydrogen bonding necessary to confer on the materials the high density, the thermal and chemical stability, and the explosive insensitivity required for new insensitive energetic materials.