Catalysis of the Diels–Alder Reaction of Furan and Methyl Acrylate in Lewis Acidic Zeolites

Abstract

Diels−Alder (DA) reactions of furans yield oxanorbornene derivatives which can be converted to a variety of molecules, ranging from molecules of biological interest to naturally occurring organic compounds, and to aromatics via dehydration, a promising alternative for the synthesis of aromatics from renewables. With furan being one of the less reactive dienes, the development of Lewis acidic heterogeneous catalysts, without the shortcomings of the traditional homogeneous catalysts, is critically important. Herein, we use computational chemistry to study the DA reaction of furan and methyl acrylate in three zeotypic Lewis acids, Sn-, Zr-, and Hf-BEA. We find that all three exhibit the same ability to enhance the electrophilic character of the dienophile and promote modest charge transfer from the diene. Despite being moderately Lewis acidic, they still achieve a reduction of about 12.5 kcal/mol in the activation energy relative to the reaction in the absence of catalyst.

Advances in Diels–Alder/aromatization of biomass furan derivatives towards renewable aromatic hydrocarbons

“…In addition, catalysts (such as Lewis acids) can influence the HOMO-LUMO gap by coordinating the HOMO or the LUMO energy of the addends and increasing the interaction between HOMO and LUMO, aiming to improve the reaction rate accordingly. [132][133][134][135] The interaction between HOMO and LUMO is the main factor that determines the ease of reaction and the regioselectivity and stereoselectivity of the DA cycloadducts. 129 Control of HOMO-LUMO interactions may be crucial for obtaining domain isomers of specific structures.…”

Valorisation of 2,5-dimethylfuran over zeolite catalysts studied by on-line FTIR-MS gas phase analysis

“…3 It has been found that the DA reaction can be catalysed by Lewis acid sites (LAS) but not Brønsted acid sites (BAS), 3,24 whereas the dehydration of the bicyclic intermediate, which cannot occur in reasonable rates uncatalysed, is facilitated by both LAS and tremendously by BAS. [24][25][26] Overall, the route to p-xylene via DACD is kinetically limited by the cycloaddition over BAS and dehydration on LAS. 22,24,27,28 Industrial production of commodity chemicals demands continuous processes and the manufacturing of BTX compounds is no exception.…”

Theoretical investigation into the effect of water on the N2O decomposition reaction over the Cu-ZSM-5 catalyst

“…53,54 For the low-level molecular mechanics (MM) layer, the universal force field (UFF) method was adopted. [55][56][57][58][59] The UFF method can effectively incorporate the extended confinement effects in zeolite catalysis. [60][61][62] The coulombic interaction between the QM and MM layers was considered by employing an electronic embedding scheme.…”