Related Experiment Video
Updated: Jul 14, 2026
13:02
Production, Crystallization, and Structure Determination of the IKK-binding Domain of NEMO
Published on: December 28, 2019
Nitroimine-encoded conformational locking: a molecular switch for planarity and stability.
Jatinder Singh1, Richard J Staples2, Jean'ne M Shreeve1
1Department of Chemistry, University of Idaho, Moscow, Idaho, 83844-2343, USA. jshreeve@uidaho.edu.
Materials Horizons
|July 13, 2026
Summary
Nitroimine groups lock NH2 motion in tetrazine frameworks, enhancing thermal stability. This connectivity-driven approach offers a new strategy for designing advanced energetic materials.
Area of Science:
- Energetic Materials Science
- Organic Chemistry
- Materials Science
Background:
- Traditional energetic material design focuses on substituent effects.
- Controlling molecular motion is key to tuning material properties.
- Tetrazine frameworks are versatile platforms for energetic materials.
Purpose of the Study:
- To investigate the role of nitroimine functionality in tetrazine frameworks.
- To explore a new strategy for controlling molecular motion and thermal stability.
- To shift energetic material design towards connectivity-driven conformational control.
Main Methods:
- Synthesis of tetrazine frameworks incorporating nitroimine groups.
- Spectroscopic analysis to confirm structural features.
- Thermal analysis (e.g., Differential Scanning Calorimetry) to assess stability.
Main Results:
- The nitroimine group acts as an intramolecular locking unit, restricting NH2 motion.
- Suppression of molecular motion leads to enhanced thermal stability.
- Demonstrated a framework-level strategy for controlling reactive molecular systems.
Conclusions:
- Connectivity-driven conformational control is a viable strategy for energetic material design.
- This approach offers an alternative to substituent-centric optimization.
- The nitroimine locking unit provides a novel method for modulating material properties.
Related Concept Videos
01:19Structure of Amines
The hybridized nitrogen atom in amines possesses a lone pair of electrons and is bound to three substituents with a bond angle of around 108°, which is less than the tetrahedral angle of 109.5°. However, the C–N–H bond angle is slightly larger at 112°, with a carbon–nitrogen bond length of 147 pm. This carbon–nitrogen bond length of of amines is longer than the carbon–oxygen bond of alcohols (143 pm) but shorter than alkanes’ carbon–carbon bond (154 pm). These aspects are illustrated in Figure...
01:58Cooperative Allosteric Transitions
Cooperative allosteric transitions can occur in multimeric proteins, where each subunit of the protein has its own ligand-binding site. When a ligand binds to any of these subunits, it triggers a conformational change that affects the binding sites in the other subunits; this can change the affinity of the other sites for their respective ligands. The ability of the protein to change the shape of its binding site is attributed to the presence of a mix of flexible and stable segments in the...
01:58Cooperative Allosteric Transitions
Cooperative allosteric transitions can occur in multimeric proteins, where each subunit of the protein has its own ligand-binding site. When a ligand binds to any of these subunits, it triggers a conformational change that affects the binding sites in the other subunits; this can change the affinity of the other sites for their respective ligands. The ability of the protein to change the shape of its binding site is attributed to the presence of a mix of flexible and stable segments in the...
01:58Cooperative Allosteric Transitions
Cooperative allosteric transitions can occur in multimeric proteins, where each subunit of the protein has its own ligand-binding site. When a ligand binds to any of these subunits, it triggers a conformational change that affects the binding sites in the other subunits; this can change the affinity of the other sites for their respective ligands. The ability of the protein to change the shape of its binding site is attributed to the presence of a mix of flexible and stable segments in the...
00:52¹H NMR of Conformationally Flexible Molecules: Temporal Resolution
At room temperature, the chair conformer of cyclohexane undergoes rapid ring flipping between two equivalent chair conformers at a rate of approximately 105 times per second. These two chair conformers are in equilibrium. The rapid ring flipping results in the interconversion of the axial proton to an equatorial proton and an equatorial to the axial proton. Such interconversions are too rapid and cannot be detected on the NMR timescale. Hence, the NMR spectrometer cannot distinguish between the...
01:25Protein Folding
Proteins are chains of amino acids linked together by peptide bonds. Upon synthesis, a protein folds into a three-dimensional conformation, critical to its biological function. Interactions between its constituent amino acids guide protein folding, and hence the protein structure is primarily dependent on its amino acid sequence.
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...
Protein Structure Is Critical to Its Biological Function
Proteins perform a wide range of biological functions such as catalyzing chemical reactions, providing...