Combinations of furoxan and 1,2,4-oxadiazole for the generation of high performance energetic materials

Abstract

Energetic materials, comprising furoxan and 1,2,4-oxadiazole backbones, were synthesized by nitrating 3,3′-bis(5-amino-1,2,4-oxadiazol-3-yl)-4,4′-azofuroxan, followed by cation metathesis, giving compounds with high density, high detonation performance and acceptable sensitivities.

Nitro-, Cyano-, and Methylfuroxans, and Their Bis-Derivatives: From Green Primary to Melt-Cast Explosives

“…The isomeric methylnitrofuroxans 1 and 2 exhibit close detonation parameters, even though 2 has a slightly higher density and formation enthalpy. These two compounds as well as other monocyclic nitro (4,11,12) and cyano-derivatives of furoxan (13,14) outperform the benchmark trinitrotoluene both in terms of the detonation velocity and heat of explosion (Table 2). 3-Methylfuroxan 15 is a surprisingly stable liquid with a moderate detonation velocity of 6.1 km s −1 .…”

“…For several species (e.g., 3,17,18,20), we combined the W1-F12 atomization energies for a symmetrical less favorable energetically conformer with the DLPNO-CCSD(T) enthalpy difference between conformers. Note that the (carbamoyl)nitro (11) and dicyano derivatives of monocyclic furoxan ( 14) are the largest species, for which the W2-F12 calculations are feasible, and the azobis derivatives of furoxan 3 and 17 are at the limit of the W1-F12 feasibility, respectively. Thus, in order to consider the nitrobenzene derivatives 5 and 8-10, the methylnitro compound 6, and dinitramine-bridged bis-methylfuroxan 19, we used a "bottom-up" ab initio computational approach.…”

“…To this end, modern synthetic approaches have shifted, e.g., from hydrocarbon backbones to strained N,O-rich heterocycles [8,9]. Among a variety of energetic patterns considered for further functionalization, the 1,2,5-oxadiazole-2-oxide (often referred to as furoxan) ring is indeed prominent due to its attractive oxygen balance, high density of energetic derivatives, and high positive enthalpy of formation [10][11][12][13][14][15][16][17][18]. Although only two positions in the furoxan ring are available for the introduction of energetic substituents, the N-oxide regioisomerism is a promising strategy for tuning the detonation performance of furoxan-based energetic materials [19][20][21][22].…”

Síntese, caracterização e atividade antitumoral in vitro de uma série de 1,2,4-oxadiazois 3,5-substituídos

“…Para concentração única, uma escala de intensidade foi utilizada para avaliar o potencial citotóxico das amostras testadas. De acordo com o percentual de inibição de crescimento celular, as amostras podem ser classificadas em amostras sem atividade (1)(2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14)(15)(16)(17)(18)(19)(20), com pouca atividade (20-50), atividade moderada (50-70) e muita atividade numa escala de citotoxidade (70-100). Adicionalmente, os experimentos serão analisados segundo suas médias e respectivos desvios no programa Graphpad Prism, feitas também pelo laboratório de Departamento de Fisiologia e Farmacologia da UFPE.…”

“…A literatura relata um conjunto diversificado de aplicações (Figura 2) para o núcleo de 1,2,4-oxadiazol na química medicinal [5,6], como antiasmático (1) [7], antidiabético (2) [8], antitumoral (3, 4 e 5) [9,10,11], anti-inflamatório (6) [12], antioxidante (7) [13] antimicrobiano (8 e 9) [14], anti-Alzheimer (10) [15,16]. Além disso, derivados de 1,2,4-oxadiazol também encontraram aplicação como cristais líquidos (11) supramoleculares e HEDMs [17,18,19].…”