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Cercosporin-Photocatalyzed [4+1]- and [4+2]-Annulations of Azoalkenes Under Mild Conditions
Published on: July 17, 2020
Calix[4]thiazole: an elusive macrocycle with coordination properties
Narendra Nath Pati1, Keita Watanabe2, Sameeta Sahoo3
1Institute for Chemical Reaction Design and Discovery (WPI-ICReDD), Hokkaido University, Kita 21, Nishi 10, Kita-ku, Sapporo, Hokkaido, 001-0021, Japan.
Chemical Communications (Cambridge, England)
|July 17, 2026
Summary
Researchers synthesized calix[4]thiazole, a novel macrocycle, using a one-pot Hantzsch condensation. This flexible molecule forms metal complexes and binds amines, showing potential in coordination chemistry.
Area of Science:
- Supramolecular Chemistry
- Organic Synthesis
- Coordination Chemistry
Background:
- Calix[4]pyrrole analogues are important in supramolecular chemistry.
- The synthesis and properties of calix[4]thiazole were previously underexplored.
- Macrocyclic compounds offer unique structural and binding properties.
Purpose of the Study:
- To synthesize calix[4]thiazole, a thiazole analogue of calix[4]pyrrole.
- To investigate the conformational flexibility and complexation behavior of the synthesized macrocycle.
- To explore the potential of calix[4]thiazole complexes in chemical sensing or catalysis.
Main Methods:
- One-pot Hantzsch condensation for macrocycle synthesis.
- Spectroscopic and crystallographic methods for characterization.
- Metal complexation studies with Zn2+, Ni2+, and Co2+.
Main Results:
- Successful synthesis of calix[4]thiazole via a one-pot Hantzsch reaction.
- Demonstrated conformational flexibility of the macrocyclic structure.
- Formation of stable cationic complexes with Zn2+, Ni2+, and Co2+.
- Observed amine binding capability in the cobalt complex.
Conclusions:
- Calix[4]thiazole is a synthetically accessible macrocycle with tunable coordination properties.
- The conformational flexibility and metal binding of calix[4]thiazole are key features.
- The cobalt complex's amine binding suggests applications in selective molecular recognition.
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