التفاصيل البيبلوغرافية
| العنوان: |
Methylaluminoxane’s Molecular Cousin: A Well-defined and “Complete” Al-Activator for Molecular Olefin Polymerization Catalysts |
| المؤلفون: |
Francesco Zaccaria (3254049), Cristiano Zuccaccia (1516378), Roberta Cipullo (2081539), Peter H. M. Budzelaar (8659065), Antonio Vittoria (4093588), Alceo Macchioni (1348728), Vincenzo Busico (1880728), Christian Ehm (1593097) |
| سنة النشر: |
2021 |
| المجموعة: |
Smithsonian Institution: Digital Repository |
| مصطلحات موضوعية: |
Biochemistry, Medicine, Microbiology, Cell Biology, Genetics, Molecular Biology, Biotechnology, Evolutionary Biology, Immunology, Developmental Biology, Cancer, Science Policy, Hematology, Virology, Computational Biology, Chemical Sciences not elsewhere classified, homodinuclear Al-cation, catalyst activation, MAO, DMA, Al i Bu 3, olefin polymerization, dichloride metallocene, cocatalyst family, i Bu 2, borate salt, olefin polymerization catalysis, Al i Bu 2, single-component cocatalyst, Molecular Olefin Polymerization Cat. |
| الوصف: |
Catalytic activity in olefin polymerization depends not only on the catalyst but also, crucially, on activator/alkylator/scavenger “packages.” Along with binary mixtures containing Lewis or Brønsted acids and Al-alkyl systems, methylaluminoxane (MAO), a still ill-defined oligomeric compound, is the only single-component cocatalyst known to fulfill all three roles effectively and simultaneously. Herein, we report a simple molecular alternative, Al-H-Al + [B(C 6 F 5 ) 4 ] − , an unusual borate salt containing a homodinuclear Al-cation ( Al-H-Al + = [ i Bu 2 (DMA)Al] 2 (μ-H) + ). Unlike the simpler [Al i Bu 2 ] + [B(C 6 F 5 ) 4 ] − , this species is easily synthesizable and stable at room temperature. Importantly, Al-H-Al + [B(C 6 F 5 ) 4 ] − can be used as a stand-alone cocatalyst for molecular olefin polymerization catalysis, representing an unprecedented molecular activator able to completely activate dichloride metallocene and prototypical post-metallocene precatalysts. Furthermore, spectroscopic and polymerization studies suggest that Al-H-Al + is the true activating species formed in situ in the binary cocatalyst [PhMe 2 NH] + [B(C 6 F 5 ) 4 ] − /Al i Bu 3 . As little as 50 equiv of Al-H-Al + [B(C 6 F 5 ) 4 ] − are required for efficient catalyst activation and impurity scavenging, orders of magnitude below the amounts usually required with MAO or Al i Bu 3 . The high, yet “tamed,” Lewis acidity of cationic Al-H-Al + is likely responsible for the increased scavenging ability. Unlike MAO, the well-defined structure of Al-H-Al + [B(C 6 F 5 ) 4 ] − offers easy avenues for further tuning, making it the prototype of a promising cocatalyst family. |
| نوع الوثيقة: |
article in journal/newspaper |
| اللغة: |
unknown |
| Relation: |
https://figshare.com/articles/journal_contribution/Methylaluminoxane_s_Molecular_Cousin_A_Well-defined_and_Complete_Al-Activator_for_Molecular_Olefin_Polymerization_Catalysts/14326636 |
| DOI: |
10.1021/acscatal.0c05696.s002 |
| الاتاحة: |
https://doi.org/10.1021/acscatal.0c05696.s002 |
| Rights: |
CC BY-NC 4.0 |
| رقم الانضمام: |
edsbas.47A35203 |
| قاعدة البيانات: |
BASE |