Abstract
Cycloolefin polymers have attracted much attention because of their high transparency and thermal stability. Late transition metal complexes are found to promote smooth and stereoselective cyclopolymerization of dienes to afford the polymers having cycloalkane groups along the polymer chain. Pd-diimine complexes initiate cyclopolymerization of the dienes to afford polymers containing trans-1,2-disubstituted cyclopentane rings. Use of Pd complexes with a C2-symmetric ligand affords polymers with highly regulated tacticity. Pd-catalyzed copolymerization of dienes with ethylene and α-olefins accompanies quantitative cyclization of each diene unit. 7-Alkyl-1,6-heptadienes undergo the cyclopolymerization with chain walking of the growing polymer catalyzed by the Pd complexes, leading to the polymers with trans-1,2-disubstituted cyclopentane groups located regularly along the linear polymer chain. The Fe and Co complexes with a bis (imino) pyridine ligand promotes the polymerization of unsubstituted 1,6-heptadienes with quantitative cyclization to yield polymers containing five-membered rings. The Fe complex-catalyzed reaction affords the polymers composed of cis-fused five-membered rings, whereas the polymerization using Co catalyst forms the polymers with trans-fused rings.
Original language | English |
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Pages (from-to) | 597-606 |
Number of pages | 10 |
Journal | Kobunshi Ronbunshu |
Volume | 64 |
Issue number | 10 |
DOIs | |
State | Published - Oct 2007 |
Externally published | Yes |
Keywords
- Chain-walking reaction
- Co complex
- Cyclocopolymerization
- Cycloolefin polymer
- Cyclopolymerization
- Fe complex
- Non-conjugated diene
- Pd complex