Document type
Journal articles
Document subtype
Full paper
Title
Probing Substrate/Catalyst Effects Using QSPR Analysis on Friedel-Crafts Acylation Reactions over Hierarchical BEA Zeolites
Participants in the publication
Ruben Elvas-Leitão (Author)
CQE
Filomena Martins (Author)
Dep. Química e Bioquímica
CQE
Leonor Borbinha (Author)
Catarina Marranita (Author)
Angela Martins (Author)
Nelson Nunes (Author)
Summary
Attempts to optimize heterogeneous catalysis often lack quantitative comparative analysis.\\\\\\\\nThe use of kinetic modelling leads to rate (k) and relative sorption equilibrium constants (K), which can be further rationalized using Quantitative Structure-Property Relationships (QSPR) based on Multiple Linear Regressions (MLR). Friedel-Crafts acylation using commercial and hierarchical BEA zeolites as heterogeneous catalysts, acetic anhydride as the acylating agent, and a set of seven substrates with different sizes and chemical functionalities were herein studied. Catalytic results were correlated with the physicochemical properties of substrates and catalysts. From this analysis, a robust set of equations was obtained allowing inferences about the dominant factors governing the processes. Not entirely surprising, the rate and sorption equilibrium constants were found to be explained in part by common factors but of opposite signs: higher and stronger adsorption forces increase reaction rates, but they also make the zeolite active sites less accessible to new reactant molecules. The most relevant parameters are related to the substrates’ molecular size, which can be associated with different reaction steps, namely accessibility to micropores, diffusion capacity, and polarizability of molecules. The relatively large set of substrates used here reinforces previous findings and brings further insights into the factors that hamper/speed up Friedel-Crafts reactions in heterogeneous media.
Date of Submisson/Request
2020-11-15
Date of Acceptance
2020-11-30
Date of Publication
2020-12-02
Where published
Molecules
Publication Identifiers
Publisher
MDPI AG
Starting page
5682
Last page
5693
Document Identifiers
DOI -
https://doi.org/10.3390/molecules25235682
URL -
http://dx.doi.org/10.3390/molecules25235682
Rankings
SCIMAGO Q2 (2019) - 0.698 - Chemistry, Miscellaneous
Web Of Science Q2 (2019) - 3.267 - Chemistry, Multidisciplinary
Keywords
QSPR analysis
Hierarchical BEA
Friedel-Crafts acylation
Kinetic modelling
Nonlinear regression
Download