Bossier, Sander

De Clerck, Karen

Dubruel, Peter

Gheysens, Tom

Gohari Derakhshandeh, Parviz

Kaczmarek, Anna

Leus, Karen

Loccufier, Eva

Van Der Voort, Pascal

English

Ghent University Academic Bibliography

ContactSander Bossier - Sander.Bossier@ugent.bewww.comoc.ugent.be - www.pbm.ugent.be - www.ugent.be/ea/match/textiles/enUniversiteit Gent@ugentGhent UniversityReferences[1] Fogg, D. E. & dos Santos, E. N. Tandem catalysis: a taxonomy and illustrative review. Coord. Chem. Rev. 248, 2365–2379 (2004).[2] Han, Q. et al. Polyoxometalate-based homochiral metal-organic frameworks for tandem asymmetric transformation of cyclic carbonates from olefins. Nat. Commun. 6, 10007 (2015).[3] De Schoenmaker, B., Van der Schueren, L., Ceylan, Ö. & De Clerck, K. Electrospun Polyamide 4.6 Nanofibrous Nonwovens: Parameter Study and Characterization. J. Nanomater. 2012, 1–9 (2012).ConclusionIn this ongoing research a proof of concept for the oxidative carboxylation of styrene by VPOM@CTF@PA-4,6 is shown. The catalytic system consists of a Vanadium-based POM that catalyzes the epoxidation of styrene to styrene oxide. The anionic POM is anchored to a cationic CTF through ion-ion interaction. It is this N-rich CTF together with the TBABr co-catalyst that allows the insertion of a CO2 molecule in the epoxide ring resulting in the formation of styrene carbonate. To more easily remove the catalyst, it is embedded in a PA-4,6 nanofiber electrospun mat. This system can be thought of as a "catalytic carpet".The next step in this research is to increase the selectivity for styrene carbonate, expand the range of olefin substrates, embed the VPOM@CTF at a high loading in the PA-4,6 mat and test the recyclability of this system.● 70 v% formic acid● 30 v% acetic acid● 15 w% PA-4,6● 10 mg CTF-1● 4 mL/h; 15 kV; 10 cm● 70 v% formic acid● 30 v% acetic acid● 15 w% PA-4,6● 10 mg CTF-1● 4 mL/h; 20 kV; 10 cm● 70 v% formic acid● 30 v% acetic acid● 15 w% PA-4,6● 10 mg CTF-1● 4 mL/h; 20 kV; 10 cmPolyamide-4,6Proof of Concept: Electrospinning CTF-1@PA-4,6VPOM@CTF SynthesisThe loading was confirmed by ICP-MS measurement. Up to 25 w% of VPOM is easily anchored in the CTF through ion-ion interaction.Proof of Concept: VPOM@CTF LoadingThe oxidative cleavage of the C-C bond of the epoxide is a well-known side reaction resulting in the formation of benzaldehyde. The styrene conversion after 48 h is already quite high, but the challenge will be to suppres this over-oxidation and mitigate the benzaldehyde formation.Standard reaction conditions● 1 mmol Chlorobenzene as internal standard● 1 mmol Styrene as substrate● Under 0,1 MPa CO2 with 0,1 mmol TBABr (32,2 mg) co-catalyst● In 3 mL Acetonitrile as solvent for 48 h at 50 °COxidative Carboxylation: Preliminary ResultsOxidative Carboxylation of StyreneIntroductionThe utilization of CO2 in the production of value-added chemicals is one way to reduce its emission. In this research, a dual-functional catalyst is envisaged to achieve the orthogonal tandem catalysis of the oxidative carboxylation of styrene to styrene carbonate [1].This is achieved by incorporating a vanadium-based polyoxometalate, [NH4]7[MnV13O38], (VPOM) in an cationic covalent triazine framework (CTF) based on imidazolium moieties. More specifically, the embedded VPOM catalyzes the epoxidation of styrene to styrene oxide with tert-butylhydroperoxide (TBHP) as the oxidant. Simultaneously, CO2 molecules are efficiently captured and activated by CO2-philic N-rich triazine groups of the CTFs [2]. Next, the bromide ion of the tetrabutylammonium bromide (TBABr) co-catalystactivates the epoxide via ring-opening. Subsequently the activated CO2 is inserted to produce the desired styrene carbonate.The goal is to make this multistep reaction go to the desired product in one reactor without the need for separation, purification, and transfer of intermediates produced.The second part of the research is focused on embedding the VPOM@CTF-particles in a polyamide-4,6 (PA-4,6) nanofiber to increase ease of use and catalyst recovery. This is achieved by electrospinning a VPOM@CTF and PA-4,6 solution in formic and acetic acid [3].(1) Department of Chemistry, Center for Ordered Materials, Organometallics & Catalysis (COMOC), Ghent University(2) Department of Organic and Macromolecular Chemistry, Polymer Chemistry & Biomaterals Group (PBM), Ghent University(3) Department of Materials, Textiles and Chemical Engineering, Centre for Textile Science and Engineering (CTSE), Ghent UniversityS. Bossier (1), P. Gohari Derakhshandeh (1), A. Kaczmarek (1), E. Loccufier (3), T. Gheysens (2), P. Van Der Voort (1), K. De Clerck (3), P. Dubruel (2) & K. Leus (1)

Orthogonal tandem oxidative carboxylation of styrene by VPOM@CTF@PA-4,6 nanofiber

https://biblio.ugent.be/publication/8608211/file/8609213

Orthogonal tandem oxidative carboxylation of styrene by VPOM@CTF@PA-4,6 nanofiber

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