Bis(tetramethylaluminate) complexes of yttrium and lanthanum supported by a quinolyl-substituted cyclopentadienyl ligand: synthesis and performance in isoprene polymerization
Quinolyl-substituted half-sandwich complexes (CpQ)Ln(AlMe4)2 (CpQ = 2,3,4,5-tetramethyl-1-(8-quinolyl)cyclopentadienyl; Ln = Y, La) were obtained in quantitative yield via protonolysis reactions utilizing HCpQ and homoleptic tetramethylaluminates Ln(AlMe4)3. X-ray structure analyses revealed that th...
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| Main Authors: | , , , |
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| Format: | Article (Journal) |
| Language: | English |
| Published: |
2010
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| In: |
Organometallics
Year: 2010, Volume: 29, Issue: 11, Pages: 2588-2595 |
| ISSN: | 1520-6041 |
| DOI: | 10.1021/om100283b |
| Online Access: | Verlag, lizenzpflichtig, Volltext: https://doi.org/10.1021/om100283b
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| Author Notes: | Rannveig Litlabø, Markus Enders, Karl W. Törnroos, and Reiner Anwander |
| Summary: | Quinolyl-substituted half-sandwich complexes (CpQ)Ln(AlMe4)2 (CpQ = 2,3,4,5-tetramethyl-1-(8-quinolyl)cyclopentadienyl; Ln = Y, La) were obtained in quantitative yield via protonolysis reactions utilizing HCpQ and homoleptic tetramethylaluminates Ln(AlMe4)3. X-ray structure analyses revealed that the quinolyl-substituted cyclopentadienyl ligand coordinates to the rare-earth metal centers in an η5:η1 fashion through the Cp ring carbon atoms and the N atom of the quinolyl substituent. The complexes (CpQ)Ln(AlMe4)2 show good activity and high trans-1,4-stereoselectivity (maximum 93%) in the polymerization of isoprene upon activation with the organoborates [Ph3C][B(C6F5)4] and [PhNMe2H][B(C6F5)4]. The effects of metal size, cocatalyst, temperature, and solvent were assessed in these polymerization reactions, and the performance of such N-donor-functionalized complexes was compared to that of (CpR)Ln(AlMe4)2 containing different types of nondonor-functionalized cyclopentadienyl ligands. |
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| Item Description: | Published online 11 May 2010 Gesehen am 29.11.2022 |
| Physical Description: | Online Resource |
| ISSN: | 1520-6041 |
| DOI: | 10.1021/om100283b |