The harsh and unselective nature of conventional nitrating agents, based on nitric-sulphuric acid mixtures or pure nitric acid, has led to the development of new nitration methodologies based on dinitrogen pentoxide (N₂O₅) that overcome many of the drawbacks of conventional media, especially when dealing with sensitive substrates. Two principal nitration systems have been developed: (i) N₂O₅ in pure nitric acid, and (ii) N₂O₅ in organic solvents, mainly chlorinated hydrocarbons. The former system possesses strength similar to mixed acid (HNO₃-H₂SO₄) systems and is therefore potent, but displays advantages such as ease of generation of the nitration reagent by electrolysis and compatibility with nitramine products, facilitating the synthesis of nitramine explosives as well as certain aromatic nitro compounds. The second system (N₂O₅/organic solvent) encompasses a much wider range of nitrations, and with suitable choice of substrate permits the generation of polynitrated species directly without the formation of acidic by-products, an important environmental consideration. These conditions are also compatible with sensitive substrates, particularly those possessing strained-ring heterocyclic skeletons; thus the nitration of such compounds with N₂O₅ permits precursors for energetic polymers (e.g. polyNIMMO) to be prepared by selective nitration. Likewise, nitrated derivatives of suitably functionalized elastomeric pre-polymers (e.g. NHTPB) can also be manufactured; both of the latter category of compound find important application as energetic binders for novel explosive and propellant compositions, notably low-vulnerability (LOVA) propellant charges.