Nitration of Azasydnones and Azasydnonimines: A Method for the Functionalization of Aryl Derivatives

Abstract

The first example of functionalization of mesoionic 3‐R‐1,2,3,4‐oxatriazol‐5‐ones and 3‐substituted‐1,2,3,4‐oxatriazol‐5‐imines (azasydnones and azasydnonimines, respectively) by the electrophilic reaction without destruction of the oxatriazole ring is reported. Nitration of a range of aryl derivatives bearing various electron donating and withdrawing substituents at the ortho‐, meta‐ and para‐positions using HNO3/H2SO4 mixtures has been assessed in order to develop an approach for the synthesis of corresponding nitroaryl derivatives. Whereas nitration occurs meta to the azasydnone ring, the regioselectivity of the electrophilic substitution can be affected by the nature of the substituent attached to the aryl ring, and a variety of polyfunctionalized derivatives can be readily accessed by using this methodology, which may have applications in the target‐oriented synthesis. The reactivity, synthesis, and structure of the mesoionic 3‐substituted‐1,2,3,4‐oxatriazole derivatives described here provide interesting new information on this known but poorly understood heterocycle.

Tetrazole Azasydnone (C2N7O2H) And Its Salts: High‐Performing Zwitterionic Energetic Materials Containing A Unique Explosophore

“…Despiteh aving thesem olecular features conducive to high performance, they have been much less studied as energetic materials. Recently,s ome beautiful work by Sheremetev et al [35] has pioneered the use of this unique heterocyclic system in energetic materials.W hile published studies on the energetic properties of azasydnones are relativelyl imited compared to other heterocyclic energetic backbones [35,36,45,[37][38][39][40][41][42][43][44] they have been explored as nitric oxide donors in pharmaceuticals. [46][47][48] Furthermore, the azasydnone ring, like the tetrazole ring can form its detonation products by pushing electrons, without needing to move atoms, an importantc riteria in the development of primary explosives.…”

Synthesis and Characterization of 3‐(5‐(Fluorodinitromethyl)‐1H‐1,2,4‐triazol‐3‐yl)‐4‐nitrofurazan: A Novel Promising Energetic Component of Boron‐based Fuels for Rocket Ramjet Engines

“…Layers are formed by anions linked through hydrogen bonds with ammonium cations and additionally stabilized by O…π interactions. Layers are rotated relative to each other and connected by shortened O…O and O…N contacts (for details, see Supporting Materials) which are commonly observed in polynitroheterocycles . In spite of the presence of the ammonium cation, crystal density of compound 6 is very high (1.910 g cm −3 at 100 K) (for details, see ESI).…”

Oxatriazoles: Potential Frameworks for Energetic Compounds?

“…Numerous oxatriazole derivatives are known [26, 27], but not – to our knowledge – the parent compounds 3 and 4 . The derivatives have been found to display a variety of biological activities.…”