Theoretical Insight into the Conversion Mechanism of Glucose to

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Theoretical Insight into the Conversion Mechanism of Glucose to Fructose Catalyzed by CrCl2 in Imidazolium Chlorine Ionic Liquids Yaru Jing, Jun Gao, Chengbu Liu, and Dongju Zhang J. Phys. Chem. B, Just Accepted Manuscript • DOI: 10.1021/acs.jpcb.6b11820 • Publication Date (Web): 14 Feb 2017 Downloaded from http://pubs.acs.org on February 15, 2017

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The Journal of Physical Chemistry

Theoretical Insight into the Conversion Mechanism of Glucose to Fructose Catalyzed by CrCl2 in Imidazolium Chlorine Ionic Liquids Yaru Jing,† Jun Gao,‡ Chengbu Liu,† and Dongju Zhang*,†

†

Key Lab of Colloid and Interface Chemistry, Ministry of Education, Institute of Theoretical Chemistry, Shandong University, Jinan, 250100, P. R. China

‡

Hubei Key Laboratory of Agricultural Bioinformatics, College of Informatics, Huazhong Agricultural University, Wuhan, 430070, P. R. China Corresponding author: Dr & ProfessorDongju Zhang E-mail: [email protected] Tel: +86-531-88365833 Fax: +86-531-88564464

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ACS Paragon Plus Environment


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Abstract To better understand the efficient transformation of glucose to fructose catalyzed by chromium chlorides in imidazolium-based ionic liquids (ILs), density functional theory calculations have been carried out on a model system which describes the catalytic reaction by CrCl2 in 1,3-dimethylimidazolium chlorine (MMImCl) ionic liquid (IL). The reaction is shown to involve three fundamental processes: ring opening, 1,2-H migration, and ring closure. The reaction is calculated to exergonic by 3.8 kcal/mol with an overall barrier of 37.1 kcal/mol. Throughout all elementary steps, both CrCl2 and MMImCl are fund to play substantial roles. The Cr center, as a Lewis acid, coordinates to two hydroxyl group oxygen atoms of glucose to bidentally rivet the substrate, and the imidazolium cation plays a dual role of proton shuttle and H-bond donor due to its intrinsic acidic property, while the Cl− anion is identified as a Brönsted/Lewis base and also a H-bond acceptor. Our present calculations emphasize that in the rate-determining step the 1,2-H migration concertedly occurs with the deprotonation of O2–H hydroxyl group, which is in nature different from the stepwise mechanism proposed in the early literature. The present results provide a molecule-level understanding for the isomerization mechanism of glucose to fructose catalyzed by chromium chlorides in imidazolium chlorine ILs.

Introduction

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The conversion of biomass to various valuable chemicals has attracted great attention due to people’s concerns for both depletion of fossil resources and global warming.1-5 To obtain efficient processes for this conversion, numerous catalytic systems have been developed in recent decades.6-9 The isomerization of glucose to fructose is a crucial intermediate step in the synthesis of various biomass-based chemicals, in particular, 5-hydroxymethylfurfural (HMF), aversatile sugar derivative and a key intermediate between biomass-based carbohydrate chemistry and petroleum-based industrial chemistry.2 It has been indicated that the overall conversion efficiency from biomass to value-added chemicals is controlled by the isomerization of glucose to fructose.10-12 This process can be catalyzed by Lewis acids13-15 or BrØnsted bases.16,17 However, the base-catalyzed transformation is in general to be less efficient than the acid-catalyzed one due to the instability of monosaccharides under alkaline conditions.18 Therefore, in recent years, the Lewis acid-catalyzed isomerization of glucose to fructose attracted remarkable attention and great progress has been achieved.19-21 In the past decades, researchers have tested the performances of various Lewis acidcatalysts for conversion of glucose to fructose, including homogenous catalysts22-25 such as metal halides and Bronsted bases, and heterogeneous catalysts27-30 such as metal oxides and Sn-beta zeolite. To date, however, the fructose yield and selectivity from glucose isomerization are not satisfactory. It is noted that the Zhang’s group31 reported a breakthrough research result that shows metal halides in 1-ethyl-3-methylimidazolium chlorine (EMImCl) ionic liquid 3



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(IL) can effectively promote the transformation of glucose to fructose and further to HMF, achieving an up to 69% yield. The yield was further increased to 81% by Binder et al.32 Following the pioneering work of Zhang and coworkers,31 many studies reported the use of IL media for the catalytic conversion of the biomass-derived sugars to various value-added chemicals.33-36 It is now believed that the combination of chromium chlorides with imidazolium chlorine ILs is a particularly active and efficient catalyst system for the isomerization of glucose.37,38 Although significant efforts have been devoted to carrying out the isomerization of glucose to fructose in the past years, our understanding for the molecular mechanism is still not complete. In particular, we noted that the theoretical study on glucose-fructose isomerization is relative rare39,40 in contrast to the numerous experimental studies.41-43 As far as we known, there is no a systematic theoretical discretion for all elementary steps involved in the most efficient glucose-fructose conversion catalyzed by chromium chlorides in imidazolium chlorine ionic liquids (ILs). In this work, we address this issue by performing density functional theory (DFT) calculations with special attention focusing on understanding the roles of chromium chloride and the IL. Computational details Scheme 1 shows the model system studied in this article, which describes the conversion of glucose to fructose catalyzed by CrCl2 in 1,3-dimethylimidazolium chloride (MMImCl), a commonly used imidazolium-based IL in biomass conversion field.39 4


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Scheme 1. Catalytic isomerization of glucose to fructose by CrCl2 in MMImCl.

The

calculations

were

carried

out

by

using

the

PBE1PBE

hybrid

exchange-correlation functional with the standard 6-31+ g (d) basis set for Cr, Cl, and O atoms, and the 6-31g(d) basis set for all other atoms, as implemented in Gaussian 09 software package.44 The PBE1PBE functional has been shown to achieve high accuracy for describing transition-metal-catalyzed reactions.45 All geometries for the intermediates and transition states were fully optimized in the gas phase without any constraints. Vibrational frequency calculations were carried out at the same level to identify the natures of all the stationary points (local minimum or first-point saddle point) and to provide Gibbs free energies at 373 K and 1atm, which include entropic contributions by taking into account the vibrations, rotations, and translations of the structures. The solvent effect of MMImCl IL was estimated by performing single-point energy calculations based on the polarizable continuum model (PCM) with a dielectric constant (ε) of 24.5546 and a radius of 3.0 Å computed from the optimized MMImCl ion pair. The intrinsic reaction coordinate (IRC)47,48 calculations have been performed to verify the connectivity of transition states and minima. All calculations are carried out on the quintet potential energy surface because both CrCl2 and its complex with glucose exhibit clear preferences for their quintet states. This is

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in agreement with the results of magnetic susceptibility measurements conducted by Pidko and co-workers.37 Results and discussion It is generally recognized that the catalytic isomerization of glucose to fructose can be divided by three stages: ring opening, H shift between C1 and C2, and ring closure, as displayed in Scheme 2. In the following sections, we show the calculated mechanism details of every elementary step in the isomerization of glucose to fructose catalyzed by CrCl2 in MMImCl.

Scheme 2. General mechanism for the isomerization of glucose to fructose.

Initial complex. For a catalytic reaction, the formation of the initial complex between substrate and catalyst is an essential step. For the present reaction under consideration, we mimic its reactivity using supermolecular cluster method: the reaction system consists of a glucose molecule, a CrCl2 molecule, and two ionic pairs of MMImCl. The initial geometry of the three component complex glucose-CrCl2-MMImCl is obtained based on a combination of chemical and electrostatic senses. For example, the Cr center coordinates to hydroxyl group oxygen atom(s) of glucose and/or Cl− anion(s) of the ionic pair, the electrostatic interaction occurs between the cation and 6


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anion, the anion docks with the hydroxyl group hydrogen atom of glucose to form the intermolecular hydrogen bonds. Although this procedure does not guarantee finding the global energetic minimum in mechanistic pathways, it provides a reasonable approach that approximately describes the reaction under consideration. Figure 1 shows two geometries of the three component complex glucose-CrCl2-MMImCl (termed 1 and 1′ ′) with different coordination structures. Structure 1 features a Cr center bound to the O1–H and O2–H hydroxyl groups of glucose along with one Cl− ligand in an axial position with two Cl− ligands in the equatorial plane. In contrast, in 1′ ′ Cr center coordinates with the O1–H hydroxyl group of glucose and three Cl− ligands in the equatorial plane.1 is identified to be more stable by 2.1 kcal/mol than 1′ ′, implying that the coordination of Cr center with O2–H hydroxyl group of glucose is energetically more favorable. In this sense, 1 was set as the zero-energy reference point in the following free energy profiles.

Figure

1.

Optimized

geometries

of

the

three

7


component

complex


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glucose-CrCl2-MMImCl. The values in parentheses refer the calculated relative free energies (in kcal/mol). Bond distances are given in Å.

Ring opening. From a chemical point of view, the ring opening process of glucose may follow two steps: the deprotonation of O1–H hydroxyl group of glucose by a Cl− anion, followed by the cleavage of the C1−O6 bond with the protonation of O6 to form an open chain form of glucose. However, we failed to obtain a transition state describing the O1 proton abstraction process. The potential energy surface scans (PES) about Cl−H distance are performed in gas and solvent. It is found that the system energies monotonously increase with decrease of Cl−H distance both in gas phase and solvent, indicating that the Cl− anion is not appropriate to directly abstract the proton from O1–H hydroxyl group. Interestingly, we located an alternative pathway for the deprotonation of O1–H hydroxyl group, where the imidazolium cation at the reactive site plays a role of H-shuttle and one of two Cl− anions serves as a Brönsted base accepting proton and another one acts a Lewis base coordinating to the chromium center to stabilize the complex. Both the cation and anion take part in the reaction. This situation is very different from the imidazolium ionic liquid-promoted conversion of fructose to 5-HMF by the group of Wang and He9, where the imidazolium bromide IL was proposed to promote the dehydration of fructose through hydrogen bond interaction. As illustrated in Figure 2, TS1-2 is indentified as the transition state, in which the proton of O1–H hydroxyl group is migrating to C2 atom of imidazolium cation and 8


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the proton at C2 is shifting towards Cl− anion. The barrier of this process is calculated to be 31.5 kcal/mol. The forward evolution of TS1-2 leads to the formation of O1-deprotonated intermediate 2 in which negative charge on O1 is effectively stabilized by a Lewis acidic Cr center.35,47 Subsequently, the protonation of O6 occurs through transition state TS2-3 to break the C1−O6 bond and form an open-chain form of glucose, denoted as intermediate 3. The free energy barrier of this step is computed to be 18.3 kcal/mol. With these two deprotonation and protonation processes, the pyranose ring of glucose is successfully opened.

Figure 2. Calculated Gibbs free energy profile with schematic geometries of intermediates and transition states for the ring opening of glucose. Bond distances are given in Å.

H shift between C2 and C1. Two potential pathways, denoted as I and II in Figure 3, 9



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have been located for the H shift process between C2 and C1. Pathway I involves two elementary steps: the deprotonation of O2–H hydroxyl group and the subsequent migration of H from C2 to C1. The calculated free energy profile for this process with schematic representation of calculated structures is shown in Figure 3. Along the reaction coordinate, 3 evolves to it’s an energetically more stable conformational isomer, 4, which is geometrically ready to carry out the deprotonation of hydroxyl group on C2 via transition state TS4-5 where the proton of O2–H hydroxyl group is shifting to C2 atom of imidazolium cation and the proton at C2 is transferring to Cl− anion, generating O2-deprotonated intermediate 5 in which negative charge on O2 is effectively stabilized by the Lewis acidic Cr center. The free energy barrier of this step is computed to be 40.8 kcal/mol. Subsequently, H migrates from C2 to C1 through transition state TS5-6 with a high free energy barrier of 45.0 kcal/mol, giving O1-deprotonated intermediate 6 in which the Lewis acidic Cr center effectively stabilizes negative charge on O1. It is clear that the free energy barriers of the above two steps is too high for a thermal reaction under mild experimental conditions. Alternatively, pathway II presents an energetically more favorable process for the H migration from C2 to C1 atom, which is a concerted process where the transfer of the proton from O2 to Cl− anion occurs with the migration of H from C2 to C1. The transition state involved in this process is TS4-7, whose relative free energy is calculated to be 37.1 kcal/mol, lower by 3.1 kcal/mol than TS4-5 and by 7.9 kcal/mol than TS5-6. The higher stabilization of TS4-7 is highly likely the less negative charge (-0.366 e) on O2 in it than those in TS4-5 (-0.653 e) and TS5-6 (-0.521 e), as shown in 10


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Figure 4. From the calculated geometries of TS4-7 (Figure 3), it is observed that the imidazolium cation severs as an H-bond donor due to its intrinsic acidic property and the Cl− anions play a role of H-bond acceptor, which is crucial for stabilizing the transition state.

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Figure 3. Calculated Gibbs free energy profiles with schematic geometries of intermediates and transition states for the H shift between C2 and C1. Bond distances are given in Å. 12


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Figure 4. Optimized Geometries of TS4-5, TS5-6 and TS4-7 with calculated Mulliken charges (blue values in e) on O2. Bond distances are given in Å.

The studies by the Hensen’s group20,21 show that the presence of a second Cr center can aid the H shift between C2 and C1. We also performed calculations using a cluster model containing two CrCl2 units, where two Cr centers are bridged by O1. As indicated in Figure 5, TS8-9, is identified as the transition state of the H shift, and its relative energy is calculated to 29.2 kcal/mol, which is comparable with the barrier value (~22 kcal/mol) reported by the Hensen’s group.20 This result indicates that the binuclear Cr complex plays a substantial role during the H shift, which remarkably stabilizes the transition state.

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Figure 5. Calculated Gibbs free energy profile for the H shift between C2 and C1 using a cluster model containing two CrCl2 units.

Ring closure. Figure 6 shows the computational results for the ring closure process, the final stage of the isomerization of glucose to fructose. This process can be characterized as three fundamental sub-processes: protonation of O1, ring closure, and protonation of O2. Along the reaction coordinate, 7 evolves to it’s an energetically more stable conformational isomer, intermediate 10. Then the protonation of O1 occurs via transition state TS10-11 where proton of HCl is moving to C2 atom of imidazolium cation and the proton at C2 is shifting to the negatively charged O1, leading to the formation of species 11. The free energy barrier of this step is computed to be 35.7 kcal/mol. To carry out the ring closure, intermediate 11 evolves into the energetically more favorable structure 12 through the reposition between the substrate 14


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and ion pair. 12 is formally (geometrically) ready to perform the ring closure. The transition state involved is located to be TS12-13 where the proton is transferring from O6 to Cl− anion with the assistance of imidazolium cation and O6−C1 bond is forming, leading to intermediate 13. As shown in Figure 6, TS12-13 (44.7 kcal/mol) is 30.5 kcal/mol less stable than TS12-14 (14.2 kcal/mol) in which the Cl− anion is directly abstracting the proton of O6 without the aid of the imidazolium cation. The relatively higher stabilization of TS12-14 can be attributed to the smaller steric repulsion and the less negative charge on O6 (Figure 7). It is obvious that the formation of O6−C2 bond weakens the strength of O6−H bond, in the light of this, it is not surprise that Cl− anion directly abstract the proton from O6 in TS12-14. In the protonation of O2 step, 14 first evolves to it’s an energetically more stable conformational isomer, intermediate 15, which is then converted into intermediate 16 through transition state TS15-16 with a barrier of 31.8 kcal/mol. As indicated by geometrical parameters shown in Figure 6, TS15-16 is the desired transition state carrying out the protonation of O2, where the proton of HCl is transferring to C2 atom of imidazolium cation while the proton at C2 is migrating to the negatively charged O2. The free energy barrier associated with this step is 31.8 kcal/mol. Again, it is observed that the imidazolium cation plays a dual role of proton shuttle and H-bond donor, and the Cl− anion severs as a Brönsted/Lewis base and also an H-bond acceptor.

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Figure 6. Calculated Gibbs free energy profiles with schematic geometries of intermediates and transition states for the ring closure. Bond distances are given in Å.

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Figure 7.

Optimized Geometries of TS12-13 and TS12-14 with calculated Mulliken

charges (blue values in e) on O6. Bond distances are given in Å

The calculated results presented above lead to the clear conclusion that the isomerization of glucose to fructose catalyzed by monomolecular CrCl2 in MMImCl is exergonic by 3.8 kcal/mol and the overall barrier of this process is calculated to be 37.1.kcal/mol. Conclusions DFT calculations have shown the mechanism details for the isomerization of glucose to fructose promoted by CrCl2 in MMImCl IL. The reaction is found to involve three fundamental processes:ring opening, 1,2-H migration, and ring closure. The 1,2-H migration is identified as a concerted process involving the deprotonation of O2–H hydroxyl group with the shift of H between C2 and C1. The catalytic reaction is carried out with associated assistance of CrCl2 and MMImCl, where the Cr center 17



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plays a role of Lewis acid by coordinating to the hydroxyl group oxygen atoms of glucose, the Cl− anion is identified as a Brönsted/Lewis base and also a H-bond acceptor, while the imidazolium cation acts a proton shuttle and H-bond donor. The present theoretical results provide a clear elementary-step mechanism profile of the isomerization of glucose to fructose assisted by chromium chlorides in imidazolium chlorine ILs. ASSOCIATED CONTENT Supporting Information Cartesian coordinate of all intermediates and transition states. The Supporting Information is available free of charge on the ACS Publications website at DOI:_________________. AUTHOR INFORMATION Corresponding Author *E-mail for D.Z.: [email protected] Notes The authors declare no competing financial interest. ACKNOWLEDGMENTS The authors acknowledge the financial support from National Natural Science Foundation of China (Nos. 21433006 and 21373124). REFERENCES 18


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(1) Chheda, J. N.; Huber, G. W.; Dumesic, J. A. Liquid-phase catalytic processing of biomass-derived oxygenated hydrocarbons to fuels and chemicals. Angew. Chem. Int. Ed. 2007, 46, 7146. (2) vanPutten, R. J.; van der Waal, J. C.; De Jong, E. D.; Rasrendra, C. B.; Heeres, H. J.; de Vries, J. G. Hydroxymethylfurfural, a versatile platform chemical made from renewable resources. Chem. Rev. 2013, 113, 1499–1597. (3) Lee, S. U.; Jung, K.; Park, G. W.; Seo, C.; Hong, Y. K.; Hong, W. H.; Chang, H. N. Bioprocessing aspects of fuels and chemicals from biomass. Korean. J. Chem. Eng. 2012, 29, 831–850. (4) Li, H. X.; Xu, W. J.; Huang, T. Y.; Jia, S. Y.; Xu, Z. W.; Yan, P. F.; Liu, X. M.; Zhang, Z. C. Distinctive aldose isomerization characteristics and the coordination chemistry of metal chlorides in 1-Butyl-3-methylimidazolium chloride. ACS. Catal.2014, 4, 4446–4454. (5) Li, Y.; Wei, Z. J.; Chen, C. J.; Liu, Y. X. Preparation of 5-Hydroxymethylfurfural by Dehydrationof Carbohydrates. Prog. Chem, 2010, 8, 1603-1609.. (6) Shi, J. C.; Liu, W. T.; Wang, N. N.; Yang, Y.; Wang, H. J. Production of 5-hydroxymethylfurfural from mono-and disaccharides in the presence of ionic liquids. Catal. Lett. 2014, 144, 252–260. (7) Kim, B.; Jeong, J.; Lee, D.; Kim, S.; Yoon, H. J.; Lee, Y. S.; Cho, J. K. Direct transformation of cellulose into 5-hydroxymethyl-2-furfural using a combination of metal chlorides in imidazolium ionic liquid. Green Chem. 2011, 13, 1503–1506. 19



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

(8) Li, H.; Zhang, Q. Y.; Liu, X. F.; Chang, F.; Zhang, Y. P.; Xue, W.; Yang, S. Immobilizing Cr3+ with SO3H-functionalized solid polymeric ionic liquids as efficient and reusable catalysts for selective transformation of carbohydrates into 5-hydroxymethylfurfural.Bioresour. Technol. 2013, 144, 21–27. (9) Li, Y. N.; Wang, J. Q.; He, L. N.; Yang, Z. Z.; Liu,A. H.; Yu,B.; Luan, C. R.Experimental and theoretical studies on imidazolium ionic liquid-promoted conversion of fructose to 5-hydroxymethylfurfural. Green Chem, 2012, 14, 2752-2758. (10) Rosatella, A. A.; Simeonov, S. P.; Frade, R. F. M.; Afonso, C. A. M. 5-Hydroxymethylfurfural (HMF) as a building block platform: Biological properties, synthesis and synthetic applications. Green Chem. 2011, 13, 754–793. (11) Loerbroks, C.; van Rijn, J.; Ruby, M. P.; Tong, Q.; Schüth, F.; Thiel, W. Reactivity of Metal Catalysts in Glucose–Fructose Conversion. Chem. Eur. J. 2014, 20, 12298–12309. (12) Stahlberg, T.; Rodriguez-Rodriguez, S.; Fristrup, P.; Riisager, A. Metal‐Free Dehydration of Glucose to 5-(Hydroxymethyl) furfural in Ionic Liquids with Boric Acid as a Promoter. Chem. Eur. J. 2011, 17, 1456–1464. (13) Wang, T. F.; Nolte, M. W.; Shanks, B. H. Catalytic dehydration of C 6 carbohydrates for the production of hydroxymethylfurfural (HMF) as a versatile platform chemical. Green Chem. 2014, 16, 548-572. (14) Li, Y. P.; Head-Gordon, M.; Bell, A. T. Analysis of the reaction mechanism and 20


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catalytic activity of metal-substituted beta zeolite for the isomerization of glucose to fructose. ACS Catal. 2014, 4, 1537-1545. (15) Moliner, M.;Román-Leshkov, Y.; Davis, M. E. Tin-containing zeolites are highly active catalysts for the isomerization of glucose in water. Proc. Natl. Acad. Sci. U. S. A. 2010, 107, 6164-6168. (16) Carraher, J. M.; Fleitman, C. N.; Tessonnier, Jean-Philippe. Kinetic and mechanistic study of glucose isomerization using homogeneous organic Brønsted base catalysts in water.ACS Catal. 2015, 5, 3162-3173. (17) Román-Leshkov, Y.; Davis. M. E. Activation of carbonyl-containing molecules with solid Lewis acids in aqueous media. AcsCatal. 2011, 1, 1566-1580. (18) Liu, C.; Carraher, J. M.; Swedberg, J. L.; Herndon, C. R.; Fleitman, C. N.; Tessonnier, J. P. Selective base-catalyzed isomerization of glucose to fructose. ACS Catal. 2014, 4, 4295–4298. (19) Vega-Vila, J. C.; Harris, J. W.; Gounder, R. Controlled insertion of tin atoms into zeolite framework vacancies and consequences for glucose isomerization catalysis. J. Catal. 2016, 344,108-120. (20) Zhang, Y. N.; Pidko, E. A.; Hensen, E. J. M. Molecular aspects of glucose dehydration by chromium chlorides in ionic liquids. Chem. Eur. J. 2011, 17, 5281-5288. (21) Pidko, E. A.; Degirmenci, V.; Hensen, E. J. M. On the mechanism of Lewis acid catalyzed glucose transformations in ionic liquids. ChemCatChem 2012, 4, 1263–1271. 21



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(22) Yang, Q.; Zhou, S. F.; Runge, T. Magnetically separable base catalysts for isomerization of glucose to fructose. J. Catal. 2015, 330, 474–484. (23) Yong, G.; Zhang, Y. G.; Ying, J. Y. Efficient Catalytic System for the Selective Production of 5-Hydroxymethylfurfural from Glucose and Fructose. Angew. Chem., Int. Ed. 2008, 47, 9345–9348. (24) Guan, J.; Cao, Q.; Guo, X. C.; Mu X. D. The mechanism of glucose conversion to 5-hydroxymethylfurfural catalyzed by metal chlorides in ionic liquid: A theoretical study. Comput. Theor. Chem. 2011, 963, 453–462. (25) Jia, S. Y.; Xu, Z. W.; Zhang, Z. C. Catalytic conversion of glucose in dimethylsulfoxide/water binary mix with chromium trichloride: Role of water on the product distribution. Chem. Eng. J. 2014, 254, 333–339. (27) Watanabe, M.; Aizawa, Y.; Iida, T.; Nishimura, R.; Inomata, H. Catalytic glucose and fructose conversions with TiO2 and ZrO2 in water at 473K: Relationship between reactivity and acid–base property determined by TPD measurement. Appl. Catal., A 2005, 295, 150–156. (28) Li, G. N.; Pidko, E. A.; Hensen, E. J. M. Synergy between Lewis acid sites and hydroxyl groups for the isomerization of glucose to fructose over Sn-containing zeolites: a theoretical perspective. Catal. Sci. Techno. 2014, 4, 2241–2250. (29) Shimizu, K. I.; Uozumi, R.; Satsuma, A. Enhanced production of hydroxymethylfurfural from fructose with solid acid catalysts by simple water removal methods. Catal. Commun. 2009, 10, 1849–1853. (30) Bermejo-Deval, R.; Orazov, M.; Gounder, R.; Hwang, S. J.; Davis, M. E. Active 22


Page 22 of 26

Page 23 of 26

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60


sites in Sn-Beta for glucose isomerization to fructose and epimerization to mannose. ACS Catal. 2014, 4, 2288–2297. (31) Zhao, H. B.; Holladay, J. E.; Brown, H.; Zhang, Z. C. Metal chlorides in ionic liquid solvents convert sugars to 5-hydroxymethylfurfural. Science 2007, 316, 1597-1600. (32) Binder J. B.; Raines R. T. Simple chemical transformation of lignocellulosic biomass into furans for fuels and chemicals. J. Am. Chem. Soc. 2009, 131, 1979-1985. (33) Van de Vyver, S.; Geboers, J.; Jacobs, P. A.;Sels, D. B. Recent advances in the catalytic conversion of cellulose. ChemCatChem 2011, 3, 82–94. (34) Ståhlberg, T.; Fu, W. J.; Woodley, J. M.;Riisager, A. Synthesis of 5-(Hydroxymethyl) furfural in Ionic Liquids: Paving the Way to Renewable Chemicals. ChemSusChem 2011, 4, 451–458. (35) Song, J. L.; Fan, H. L.; Ma, J.;Han, B. X. Conversion of glucose and cellulose into value-added products in water and ionic liquids. Green Chem. 2013, 15, 2619–2635. (36) Siankevich, S.; Fei, Z. F.; Scopelliti, R.; Laurenczy, G.; Katsyuba, S.; Yan, N.; Dyson, P. J. Enhanced Conversion of Carbohydrates to the Platform Chemical 5-Hydroxymethylfurfural Using Designer Ionic Liquids. ChemSusChem 2014, 7, 1647–1654. (37) Pidko, E. A.; Degirmenci, V.; van Santen, R. A.;Hensen, E. J. M. Glucose activation by transient Cr2+ dimers. Angew. Chem., Int. Ed. 2010, 49, 23



1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 24 of 26

2530–2534. (38) Saravanamurugan, S.; Paniagua, M.;Melero, J. A.;Riisager, A. Efficient isomerization of glucose to fructose over zeolites in consecutive reactions in alcohol and aqueous media.J. Am. Chem. Soc. 2013, 135, 5246-5249. (39) Yang, Y.; Liu, W. T.; Wang, N. N.; Wang, H. J.; Wei, Li.; Song, Z. X. Effect of Different Ionic Liquids on 5-Hydroxymethylfurfural Preparation from Glucose in DMA over AlCl3: Experimental and Theoretical Study. Chin. J. Chem. 2015, 33, 583–588. (40) Li, J. J.; Li, J. H.; Zhang, D. J.; Liu, C. B. Theoretical Elucidation of Glucose Dehydration to 5-Hydroxymethylfurfural Catalyzed by a SO3H-Functionalized Ionic Liquid. J. Phys. Chem. B 2015, 119, 13398–13406. (41) Lee, G.; Jeong, Y.; Takagaki, A.; Jung, J. C. Sonication assisted rehydration of hydrotalcite catalyst for isomerization of glucose to fructose. J. Mol. Catal. A: Chem. 2014, 393, 289–295. (42) Choudhary, V.; Pinar, A. B.; Lobo, R. F.; Vlachos, D. G.; Sandler, S. I. Comparison

of

Homogeneous

and

Heterogeneous

Catalysts

for

Glucose-to-Fructose Isomerization in Aqueous Media. ChemSusChem 2013, 6, 2369–2376. (43) Liu, L.; Xia, N, Du, J. M.; He, Q. G.; Qin, Y.; Li, H. H.; Li, C. C. A simple and rapid method for probing of isomerization of glucose to fructose with ferroceneboronic acid. Int. J. Electrochem. Sci. 2013, 8, 9163–9170. (44) Frisch, M. J.; Trucks, G. W.; Schlegel, H. B.; Scuseria, G. E.; Robb, M. A.; 24


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Cheeseman, J. R.; Scalmani, G.; Barone, V.; Mennucci, B.; Petersson, G. A. et al. Gaussian 09, Revision B.01, Gaussian, Inc., Wallingford CT, 2009. (45) Adamo, C.; Barone, V. Toward reliable density functional methods without adjustable parameters: The PBE0 model. J. Chem. Phys.1999, 110, 6158–6170. (46) Zhang, Z. C. Catalysis in ionic liquids. Adv. Catal. 2006, 49, 153–237. (47) Fukui, K. The path of chemical reactions-the IRC approach.Acc. Chem. Res. 1981, 14, 363–368. (48) Barone, V.; Cossi. M. Quantum calculation of molecular energies and energy gradients in solution by a conductor solvent model. J. Phys. Chem. A 1998, 102, 1995–2001.

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Theoretical Insight into the Conversion Mechanism of Glucose to

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