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Synthesis of Monodisperse Cylindrical Nanoparticles via Crystallization-driven Self-assembly of Biodegradable Block Copolymers
Published on: June 20, 2019
Rare-earth amidate complexes. Easily accessed initiators for epsilon-caprolactone ring-opening polymerization
Louisa J E Stanlake1, J David Beard, Laurel L Schafer
1Department of Chemistry, University of British Columbia, 6174 University Boulevard, Vancouver, British Columbia V6T 1Z3, Canada.
Inorganic Chemistry
|August 20, 2008
Summary
Researchers synthesized novel yttrium amidate complexes, yielding crystalline monomers. These complexes show high activity in initiating epsilon-caprolactone ring-opening polymerization, producing high molecular weight polymers.
Area of Science:
- Organometallic Chemistry
- Polymer Chemistry
Background:
- Yttrium amidate complexes are valuable in synthesis.
- Developing efficient catalysts for polymerization is crucial.
Purpose of the Study:
- To synthesize and characterize novel yttrium amidate complexes.
- To evaluate their catalytic activity in ring-opening polymerization.
Main Methods:
- Direct synthesis via reaction of amide proligands and Y(N(SiMe3)2)3.
- Crystallization, X-ray diffraction, and NMR spectroscopy for characterization.
- Ring-opening polymerization of epsilon-caprolactone.
Main Results:
- High-yielding preparation of crystalline, monomeric yttrium amidate complexes.
- Structural determination of tris(N-2',6'-diisopropylphenyl(naphthyl)amidate)yttrium mono(tetrahydrofuran) as a 7-coordinate C1 symmetric structure.
- Demonstrated high activity in initiating epsilon-caprolactone polymerization, yielding high molecular weight polymer.
Conclusions:
- Novel yttrium amidate complexes can be readily synthesized and characterized.
- These complexes are promising catalysts for efficient ring-opening polymerization.
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