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Published on: September 28, 2022
A New Nitrogen-Rich Energetic Material with So Many Tautomers
Fatemeh Safari1, Emmanuele Parisi2, Emin Varghese3
1Department of Physics, University of Illinois Chicago, Chicago, Illinois 60607, United States.
Crystal Growth & Design
|July 28, 2026
Summary
A novel nitrogen-rich compound, TTT1, exhibits complex acid-base and tautomeric behavior. Its energetic perchlorate salt demonstrates remarkable thermal and impact stability, crucial for energetic materials applications.
Area of Science:
- Materials Science
- Energetic Materials
- Organic Chemistry
Background:
- Nitrogen-rich compounds are of interest for energetic materials due to their high heats of formation.
- Understanding the acid-base and tautomeric properties of novel compounds is essential for predicting their behavior and potential applications.
Purpose of the Study:
- To synthesize and characterize a new nitrogen-rich triazolo-triazole compound, TTT1.
- To investigate the acid-base and tautomeric behavior of TTT1 across a wide pH range.
- To evaluate the properties of TTT1 salts, particularly their energetic performance and stability.
Main Methods:
- Synthesis of the triazolo-triazole compound TTT1.
- Acid-base titration and potentiometric measurements to determine protonation and deprotonation constants.
- Computational analysis (DFT) to predict tautomeric forms and their energies.
- Crystallization and characterization of TTT1 salts (chloride, bromide, perchlorate).
- Thermal analysis (DSC/TGA) and sensitivity testing (impact, friction, ESD) of the energetic perchlorate salt.
- Single-crystal X-ray diffraction to determine the crystal structure of the perchlorate salt up to 2.8 GPa.
Main Results:
- TTT1 can accept up to two protons and release one proton in the pH range of 0.3-12.
- Computational studies predicted four tautomers for the monocation within a narrow energy range.
- Two predicted tautomers (2H-7H-8H and 3H-7H-8H) were isolated in crystalline salts.
- The most stable predicted tautomer (1H-3H-7H) was not observed in the crystallized salts.
- The energetic perchlorate salt (3H-7H-8H tautomer) exhibited excellent thermal stability and low sensitivity to impact, friction, and electric discharge.
- X-ray diffraction of the perchlorate salt up to 2.8 GPa showed no phase transitions or decomposition, indicating high structural integrity.
Conclusions:
- TTT1 displays versatile acid-base and rich tautomeric behavior, influenced by pH and counterion.
- The energetic perchlorate salt of TTT1 demonstrates significant potential as a stable and safe energetic material.
- The discrepancy between predicted and crystallized tautomers highlights the complexity of tautomerism in solution and solid states.
- The high structural stability under pressure further supports the potential of this compound in energetic applications.
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