Title
Aluminum Alkoxy-Catalyzed Biomass Conversion Of Glucose To 5-Hydroxymethylfurfural: Mechanistic Study Of The Cooperative Bifunctional Catalysis
Abstract
Density functional theory calculations were performed to understand the detailed reaction mechanism of aluminum alkoxy-catalyzed conversion of glucose to 5-hydroxymethylfurfural (HMF) using Al(OMe)(3) as catalyst. Potential energy surfaces were studied for aggregates formed between the organic compounds and Al(OMe)(3) and effects of the medium were considered via continuum solvent models. The reaction takes place via two stages: isomerization from glucose to fructose (stage I) and transformation of fructose to HMF (stage II). Stage II includes three successive dehydrations, which begins with a 1,2-elimination to form an enolate (i.e., B), continues with the formation of the acrolein moiety (i.e., D), and ends with the formation of the furan ring (i.e., HMF). All of these steps are facilitated by aluminum alkoxy catalysis. The highest barriers for stage I and stage II are 23.9 and 31.2 kcal/mol, respectively, and the overall catalytic reaction is highly exothermic. The energetic and geometric results indicate that the catalyzed reaction path has feasible kinetics and thermodynamics and is consistent with the experimental process under high temperature (i.e., 120 degrees C). Remarkably, the released water molecules in stage II act as the product, reactant, proton shuttle, as well as stabilizer in the conversion of fructose to HMF. The metal-ligand functionality of the Al(OMe)(3) catalyst, which combines cooperative Lewis acid and Lewis base properties and thereby enables proton shuttling, plays a crucial role in the overall catalysis and is responsible for the high reactivity. (c) 2019 Wiley Periodicals, Inc.
Year
DOI
Venue
2019
10.1002/jcc.25812
JOURNAL OF COMPUTATIONAL CHEMISTRY
Keywords
DocType
Volume
DFT calculations, reaction mechanism, glucose, HMF, aluminum alkoxy catalyst
Journal
40
Issue
ISSN
Citations 
16
0192-8651
0
PageRank 
References 
Authors
0.34
0
6
Name
Order
Citations
PageRank
Qing Wang134576.64
Mingxing Fu201.01
Xiaojun Li300.34
Runfeng Huang400.34
Rainer Glaser511.06
Lili Zhao600.34