Exploring the conformational space of cobalt(III)-salen catalyst for CO2 /epoxide copolymerization: Effect of quaternary ammonium salts on preference of alternative isomers.
Karol DyduchMonika Srebro-HooperBun Yeoul LeeArtur MichalakPublished in: Journal of computational chemistry (2018)
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.
Keyphrases
- molecular dynamics
- room temperature
- ionic liquid
- density functional theory
- highly efficient
- reduced graphene oxide
- metal organic framework
- molecular dynamics simulations
- carbon dioxide
- randomized controlled trial
- visible light
- air pollution
- high resolution
- particulate matter
- electronic health record
- machine learning
- deep learning
- molecular docking
- artificial intelligence
- risk assessment