3,3'-Bi(1,2,4-oxadiazoles) featuring the fluorodinitromethyl and trinitromethyl groups

Area of Science:

• Energetic Materials Science
• Organic Synthesis
• Crystallography

Background:

• 3,3'-bi(1,2,4-oxadiazole) derivatives are explored for their energetic properties.
• Hydrogen-free compounds are desirable for enhanced stability and performance.

Purpose of the Study:

• To synthesize and characterize new hydrogen-free 3,3'-bi(1,2,4-oxadiazole) derivatives.
• To investigate the structural, thermal, and energetic properties of these novel compounds.

Main Methods:

• Synthesis of 5,5'-Bis(fluorodinitromethyl)-3,3'-bi(1,2,4-oxadiazole) and 5,5'-bis(trinitromethyl)-3,3'-bi(1,2,4-oxadiazole).
• Characterization using NMR, IR, Raman spectroscopy, elemental analysis, and mass spectrometry.
• X-ray diffraction for crystal structure determination.
• Differential scanning calorimetry (DSC) and impact/friction tests for stability and sensitivity.
• Computational analysis using EXPLO5 for detonation and propulsion parameters.

Main Results:

• Successful synthesis of two hydrogen-free 3,3'-bi(1,2,4-oxadiazole) derivatives.
• Isolation of 5,5'-dimethyl-3,3'-bi(1,2,4-oxadiazole) as a new intermediate.
• Crystal structures determined for dimethyl and fluorodinitromethyl derivatives.
• High densities and good thermal stability observed for energetic compounds.
• Computed detonation and propulsion parameters indicate potential high performance.

Conclusions:

• The synthesized hydrogen-free bi(oxadiazole) derivatives represent promising energetic materials.
• Their high densities and thermal stability, coupled with calculated performance metrics, warrant further investigation.
• This research contributes to the development of advanced explosives and propellants.