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Reversible [4 + 2] Photooxygenation in Anion-Coordination-Driven-Assembled A2L2-Type Complexes
Chaochao Fan1, Yue Wang1, Jie Zhao1
1Key Laboratory of Synthetic and Natural Functional Molecule of the Ministry of Education, College of Chemistry and Materials Science, Northwest University, Xi'an 710069, China.
Inorganic Chemistry
|January 20, 2022
Summary
Novel bis-bis(urea) ligands facilitate the creation of sulfate complexes that store singlet oxygen via photooxygenation. These endoperoxide complexes can be reverted to their original states, demonstrating a reversible oxygen storage system.
Area of Science:
- Supramolecular Chemistry
- Photochemistry
- Materials Science
Background:
- Designing photoactive molecules for specific functions is crucial in supramolecular chemistry.
- Anthracene derivatives are known for their photochemical reactivity, including photooxygenation.
Purpose of the Study:
- To design and synthesize novel bis-bis(urea) ligands incorporating a photoactive 9,10-diphenylanthracene unit.
- To construct anion-coordination-driven assemblies using these ligands and sulfate anions.
- To investigate the photooxygenation of these assemblies for potential singlet oxygen storage.
Main Methods:
- Ligand design and synthesis.
- Coordination chemistry to form sulfate complexes.
- [4 + 2] photooxygenation reactions.
- X-ray crystallography, NMR, UV-vis spectroscopy, and mass spectrometry for structural characterization.
Main Results:
- Two bis-bis(urea) ligands, L1 and L2, were synthesized.
- Sulfate complexes [TEA]4[(SO4)2(L1)2] (1) and [TEA]4[(SO4)2(L2)2] (2) were successfully formed.
- Photooxygenation yielded endoperoxide products (1-EPO and 2-EPO), which showed partial thermal reversibility.
Conclusions:
- The designed ligands enable the formation of anion-coordination-driven assemblies.
- These assemblies can undergo reversible photooxygenation, indicating potential for singlet oxygen storage.
- Structural characterization confirmed the formation and transformation of the complexes and photoproducts.
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