Related Experiment Video
Updated: Aug 22, 2025
14:11
Synthesis of pH Dependent Pyrazole, Imidazole, and Isoindolone Dipyrrinone Fluorophores using a Claisen-Schmidt Condensation Approach
Published on: June 10, 2021
6.3K
[1,4]Ditellurino[2,3-b:5,6-b']di-pyrazine
Donna Franklin1, Aundrea Lee1, Frank R Fronczek2
1Department of Chemistry, Lafayette, LA 70403, USA.
Iucrdata
|November 7, 2022
Summary
The first heavy chalcogen-containing [1,4]ditellurino[2,3-b:5,6-b]dipyrazine exhibits a folded structure due to larger tellurium atoms. Intermolecular interactions form spiral supramolecular assemblies.
Area of Science:
- Materials Science
- Crystallography
- Inorganic Chemistry
Background:
- Heterocyclic compounds containing chalcogens are crucial in materials science.
- Previous studies focused on lighter chalcogen analogs, leaving heavy chalcogen systems underexplored.
Purpose of the Study:
- To synthesize and characterize the first [1,4]ditellurino[2,3-b:5,6-b]dipyrazine, incorporating heavy chalcogens.
- To investigate the structural and intermolecular properties of this novel compound.
Main Methods:
- Single-crystal X-ray diffraction analysis was employed to determine the molecular and crystal structure.
- Analysis of bond lengths, dihedral angles, and intermolecular contacts.
Main Results:
- The compound C8H4N4Te2, [1,4]ditellurino[2,3-b:5,6-b]dipyrazine, was successfully synthesized and characterized.
- Unlike its planar sulfur analog, this molecule is folded along the Te⋯Te axis with a dihedral angle of 57.9°.
- Intermolecular Te⋯N contacts (2.894–2.963 Å) lead to the formation of spiral supramolecular assemblies and helical columns.
Conclusions:
- The incorporation of heavy chalcogens (tellurium) significantly influences the molecular geometry, leading to a non-planar structure.
- The observed intermolecular Te⋯N interactions are key to the formation of extended supramolecular architectures.
- This study expands the scope of [1,4]chalcogenadipyrazines and highlights the role of heavy chalcogens in crystal engineering.
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