Several energy-rich bifuroxans incorporating nitro and azido functionalities have been synthesized and thoroughly characterized by IR and multinuclear NMR spectroscopy, elemental analyses, single-crystal X-ray diffraction, and differential scanning calorimetry. N-oxide regiochemistry was employed to design the tunable azido(nitro)bifuroxans with different physicochemical and energetic properties. All synthesized compounds have high enthalpies of formation (449−777 kJ mol −1 ) and attractive performances, as evidenced by the high detonation velocities (8.95−9.75 km s −1 ) and Champan−Jouguet pressures (35−45 GPa). The most powerful energetic material in this series is 4,4′-dinitro-3,3′-bifuroxan. This hydrogen-free molecule (C 4 N 6 O 8 ) exhibits an outstanding heat of explosion value of 15.3 kJ cm −1 , far exceeding the top energetic material hexanitrohexaazaisowurtzitane CL-20. At the same time, the impact and friction sensitivities of 4,4′-dinitro-3,3′-bifuroxan were deemed acceptable for practical use. Overall, 4,4′-dinitro-3,3′-bifuroxan breaks a general trend called the "energy-sensitivity rule", which describes a linear increase of the mechanical sensitivity with a growth of the energetic content of the molecule, and, thus, offers great promise for future applications.

A series of novel energetic materials comprising of azo-bridged furoxanylazoles enriched with energetic functionalities was designed and synthesized. These high-energy materials were thoroughly characterized by IR and multinuclear NMR ( 1 H, 13 C, 14 N) spectroscopy, high-resolution mass spectrometry, elemental analysis, and differential scanning calorimetry (DSC). The molecular structures of representative amino and azo oxadiazole assemblies were additionally confirmed by single-crystal X-ray diffraction and X-ray powder diffraction. A comparison of contributions of explosophoric moieties into the density of energetic materials revealed that furoxan and 1,2,4-oxadiazole rings are the densest motifs while the substitution of the azide and amino fragments on the nitro and azo ones leads to an increase of the density. Azo bridged energetic materials have high nitrogen-oxygen contents (68.8-76.9 %) and high thermal stability. The synthesized compounds exhibit good experimental densities (1.62-1.88 g cm À 3 ), very high enthalpies of formation (846-1720 kJ mol À 1 ), and, as a result, excellent detonation performance (detonation velocities 7.66-9.09 km s À 1 and detonation pressures 25.0-37.7 GPa). From the application perspective, the detonation parameters of azo oxadiazole assemblies exceed those of the benchmark explosive RDX, while a combination of high detonation performance and acceptable friction sensitivity of azo(1,2,4-triazolylfuroxan) make it a promising potential alternative to PETN.

A mini-review covers recent successes in the synthesis of (S)-1,1′-binaphthyl-2,2′-diamine (BINAM) using Pd(0)-catalyzed amination reactions. As a result, versatile compounds with C2-chiral backbone were synthesized, among them are derivatives bearing additional chiral amino and fluorophore groups like dansyl amide, 7-methoxycoumarin, 6-aminoquinoline, different macrocyclic compounds with oxadiamine and polyamine linkers were obtained as well. BINAM derivatives of various structures were evaluated as fluorescent enantioselective detectors for a series of model amino alcohols. Many of them were shown to be efficient in sensing certain enantiomers of the amino alcohols by selective changes in the emission in the presence of these analytes. Small changes in the structure of the BINAM derivatives lead to serious difference in the recognition ability of the compounds under investigation.

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