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Published on: February 7, 2019
Sterically variable dizinc complexes bearing bis(iminopyridyl)phenolate ligands: synthesis, structures and reactivity
Yohan D M Champouret1, William J Nodes, Jason A Scrimshire
1Department of Chemistry, University of Leicester, University Road, Leicester, UK LE1 7RH.
Dalton Transactions (Cambridge, England : 2003)
|October 12, 2007
Summary
New chiral dizinc complexes were synthesized and characterized. These complexes show modest activity in activating ring-opening polymerization of epsilon-caprolactone, indicating potential applications in catalysis.
Area of Science:
- Coordination Chemistry
- Organometallic Chemistry
- Catalysis
Background:
- Chiral metal complexes are crucial in asymmetric synthesis and catalysis.
- Zinc complexes offer tunable electronic and steric properties for catalytic applications.
- Understanding the structure-activity relationship of dizinc complexes is essential for catalyst design.
Purpose of the Study:
- To synthesize and characterize a series of novel chiral dizinc complexes.
- To investigate the structural diversity of these dizinc complexes through single-crystal X-ray diffraction.
- To evaluate the catalytic activity of the synthesized complexes in the ring-opening polymerization of epsilon-caprolactone.
Main Methods:
- Template synthesis of chiral dizinc complexes using Schiff base pro-ligands and zinc dichloride.
- Isolation and characterization of pro-ligands and dizinc complexes.
- Single crystal X-ray diffraction for structural elucidation.
- Evaluation of catalytic activity in ring-opening polymerization of epsilon-caprolactone.
Main Results:
- Convenient synthesis of chiral dizinc complexes with varying aryl substituents on the pro-ligand.
- Structural characterization revealed diverse coordination environments, including chloride, acetate, dibenzoylmethanato, hydroxide, and pyridonate bridging ligands.
- Single crystal X-ray diffraction confirmed Zn-Zn distances in the range of 3.069(4)-4.649(6) Å.
- The complexes and mixtures demonstrated modest activation of epsilon-caprolactone ring-opening polymerization.
Conclusions:
- A versatile synthetic route to chiral dizinc complexes with tunable structures was established.
- The structural diversity highlights the adaptability of the dizinc core to different bridging ligands.
- The observed modest catalytic activity suggests potential for further development of these complexes as catalysts for ring-opening polymerization.
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