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Updated: May 23, 2026
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Solid-phase Synthesis of [4.4] Spirocyclic Oximes
Published on: February 6, 2019
Thermally driven tetrazine-to-triazole ring contraction mediated by hydroxylammonium cations
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
|May 22, 2026
Summary
Nitroimine-functionalized tetrazines show cation-dependent reactions. Hydroxylamine triggers a unique tetrazine-to-triazole transformation, unlike ammonia or hydrazine, due to the hydroxylammonium cation
Area of Science:
- Organic chemistry
- Supramolecular chemistry
Background:
- Tetrazines are nitrogen-rich heterocycles with diverse applications.
- Functionalization of tetrazines can tune their reactivity and properties.
Purpose of the Study:
- To investigate the cation-dependent reactivity of a nitroimine-functionalized tetrazine.
- To explore the influence of different cations on reaction pathways and product formation.
Main Methods:
- Synthesis of a nitroimine-functionalized tetrazine.
- Reaction studies with ammonia, hydrazine, and hydroxylamine.
- Spectroscopic and structural analysis of reaction products.
Main Results:
- The nitroimine-functionalized tetrazine displayed distinct reactivity with different nucleophiles.
- Ammonia and hydrazine formed stable salts with the tetrazine.
- Hydroxylamine induced a thermally driven transformation of the tetrazine to a triazole derivative.
Conclusions:
- The hydroxylammonium cation plays a critical role in directing the reactivity of the nitroimine-functionalized tetrazine.
- Intermolecular organization governed by the hydroxylammonium cation leads to divergent reaction pathways.
- This study highlights the potential for controlled transformations of tetrazines through cation-specific interactions.
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