Exploring the conformational space of cobalt(III)-salen catalyst for CO2 /epoxide copolymerization : Effect of quaternary ammonium salts on preference of alternative isomers
© 2018 Wiley Periodicals, Inc.
Veröffentlicht in: | Journal of computational chemistry. - 1984. - 39(2018), 23 vom: 05. Sept., Seite 1854-1867 |
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1. Verfasser: | |
Weitere Verfasser: | , , |
Format: | Online-Aufsatz |
Sprache: | English |
Veröffentlicht: |
2018
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Zugriff auf das übergeordnete Werk: | Journal of computational chemistry |
Schlagworte: | Journal Article CO2/epoxide copolymerization Co(III)-salen complexes bifunctional Co(III) catalysts cisβ/trans complexes conformational space |
Zusammenfassung: | © 2018 Wiley Periodicals, Inc. Model catalysts for CO2 /epoxide copolymerization based on Co(III) complexes were studied, with focus on the preference of their alternative isomers, cisβ vs. trans. The systems range from model structures without the co-catalyst, as derived from crystallographic data, to complex models with two (CH2 )4 N+ R3 co-catalyst chains (R = Me, Bu) grafted onto a Co(III)-salcy core. To explore the conformational space of the latter complexes, a computational protocol was developed, combining a systematic model-building approach with static and molecular dynamics calculations, and multilevel energy assessment (PM7 and DFT). Results demonstrate an influence of the co-catalyst on the relative stability of the isomers. The cisβ isomer is preferred for complexes without N+ -chains and the cisβ ↔ trans isomerization is feasible. Five-coordinate species and open-shell electronic configurations are energetically disfavored. The cisβ preference decreases with the introduction and enlargement of (CH2 )4 N+ R3 : both isomers can be populated for R = Me, while the trans isomer is visibly preferred for R = Bu. © 2018 Wiley Periodicals, Inc |
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Beschreibung: | Date Revised 20.11.2019 published: Print-Electronic Citation Status PubMed-not-MEDLINE |
ISSN: | 1096-987X |
DOI: | 10.1002/jcc.25358 |