Energetic 1,2,4-oxadiazoles: synthesis and properties

The study of high-energy materials based on poly nitrogen- and nitrogen-oxygen-containing heterocycles is one of the most important and relevant modern interdisciplinary research areas at the intersection of organic and physical chemistry and materials science. Among such heterocycles, 1,2,4-oxadiazole ring is a rather interesting building block for the synthesis of new energetic compounds. Although the chemistry of 1,2,4-oxadiazoles has been developed for more than 100 years, high-energy materials based on these heterocycles have only recently become known and are currently one of the "hot spots" in this field of science. This review systematizes recently published methods for the synthesis and features of the reactivity of 1,2,4-oxadiazole-based energetic compounds. Mono- and bis(1,2,4-oxadiazoles) as well as structures containing other azoles such as pyrazole, 1,2,5-oxadiazole, 1,3,4-oxadiazole, 1,2,3-triazole, 1,2,4-triazole and tetrazole are considered. For the series of structurally similar compounds, their physicochemical properties are summarized and the factors affecting a particular parameter are discussed.Bibliography — 123 references.