Center for Molecular Modeling - J. Bomon

Confined hot-pressurized water in Brønsted-acidic beta zeolite speeds up the O-demethylation of guaiacol

massimo — Thu, 24 Nov 2022 13:15:33 +0000

M. Bocus, E. Van den Broeck, X. Wu, M. Bal, J. Bomon, L. Vanduyfhuys, B. F. Sels, B. U. W. Maes, V. Van Speybroeck

Nature Catalysis

8, 33-45

2025

Abstract

Biorefinery technologies that convert lignin into platform chemicals are essential to reduce our future dependence on fossil resources. In these technologies, a key process is the acid-catalysed O-demethylation of guaiacol derivatives in hot-pressurized water using Brønsted mineral acids or microporous zeolites. The fundamental understanding of how hydronium ions behave in a confined environment versus bulk is still limited. Here we investigate the O-demethylation of guaiacol in hot-pressurized water with HCl or H-BEA zeolite catalysts to elucidate the impact of zeolite microporosity on reaction mechanisms and rates. Operando molecular simulations combined with experimental kinetic studies reveal that, regardless of the catalyst type, O-demethylation follows a concerted O-activated S_N2 mechanism. The reaction rate is higher in the zeolite due to more active, under-coordinated hydronium ions. Additionally, the molecular organization of solvent and reactants around the confined active site plays a crucial role in modulating the association of the reacting species and the reaction kinetics.

DOI

https://doi.org/10.1038/s41929-024-01282-6

Private attachment

Bocus_et_al-2025-Nature_Catalysis.pdf

Brønsted Acid Catalyzed Tandem Defunctionalization of Biorenewable Ferulic acid and Derivates into Bio-catechol

samuel — Fri, 10 Jan 2020 13:57:03 +0000

J. Bomon, E. Van den Broeck, M. Bal, Y. H. Liao, S. Sergeyev, V. Van Speybroeck, B. F. Sels, B. U. W. Maes

Angewandte Chemie int. Ed.

59 (8), 3063-3068

2020

Abstract

An efficient conversion of biorenewable ferulic acid into bio‐catechol has been developed. The transformation comprises two consecutive defunctionalizations of the substrate, that is, C−O (demethylation) and C−C (de‐2‐carboxyvinylation) bond cleavage, occurring in one step. The process only requires heating of ferulic acid with HCl (or H2SO4) as catalyst in pressurized hot water (250 °C, 50 bar N2). The versatility is shown on a variety of other (biorenewable) substrates yielding up to 84 % di‐ (catechol, resorcinol, hydroquinone) and trihydroxybenzenes (pyrogallol, hydroxyquinol), in most cases just requiring simple extraction as work‐up.

DOI

https://doi.org/10.1002/anie.201913023

Private attachment

Bomon_et_al-2019-Angewandte_Chemie.pdf

Towards a realistic modeling of complex zeolite-catalyzed reactions: the case of guaiacol demethylation

massimo — Thu, 30 Jun 2022 07:53:39 +0000

M. Bocus, E. Van den Broeck, M. Bal, X. Wu, J. Bomon, L. Vanduyfhuys, B. U. W. Maes, B. F. Sels, V. Van Speybroeck

ISBN/ISSN:

Talk

Conference / event / venue

ICTAC 2022

Lyon, France

Monday, 13 June, 2022 to Friday, 17 June, 2022

Abstract (private)

BOCUS_Massimo_ictac2022.pdf

Transformation of aromatic biorefinery products into building blocks for fine chemicals

samuel — Fri, 10 Jan 2020 15:35:16 +0000

J. Bomon, E. Blondiaux, E. Van den Broeck, P. Mampuys, V. Van Speybroeck, B. F. Sels, B. U. W. Maes

ISBN/ISSN:

Talk

Conference / event / venue

23rd Merck Organic Chemistry Symposium

Belgium (Blankenberge)

Thursday, 5 December, 2019 to Friday, 6 December, 2019

Abstract (private)

MOCS_2019_Jeroen Bomon.pdf