Mechanistic insights into the conversion of biorenewable levoglucosanol to dideoxysugars

Mingxia Zhou; Siddarth H. Krishna; Mario De Bruyn; Bert M. Weckhuysen; Larry A. Curtiss; James A. Dumesic; George W. Huber; Rajeev S. Assary

doi:10.1021/acssuschemeng.0c06315

Mechanistic insights into the conversion of biorenewable levoglucosanol to dideoxysugars

Mingxia Zhou
, Siddarth H. Krishna
, Mario De Bruyn
, Bert M. Weckhuysen
, Larry A. Curtiss
, James A. Dumesic
, George W. Huber
, Rajeev S. Assary^*

^*Corresponding author for this work

The University of Chicago
University of Wisconsin-Madison

Research output: Contribution to journal › Article › Academic › peer-review

Abstract

A molecular understanding of the conversion of biorenewable threo- and erythro-levoglucosanol (LGOL) to 3,4-dideoxysugars in aqueous medium is provided based on first-principles simulations. The synthetic importance of this transformation is that these intermediates can be quantitatively hydrogenated to (S,S)/(S,R) hexane-1,2,5,6-tetrol (tetrol), whose stereochemistry depends on which dideoxy sugar intermediates are formed during LGOL conversion. The thermodynamic and kinetic feasibility of the acetal (R2C(OR)2) hydrolysis in LGOL is investigated via computing the free energy profile. In aqueous medium, the rate-determining step of LGOL hydrolysis is the protonation of the anhydro-bridge oxygen atom of LGOL concurrent with ring opening, yielding the cyclic forms of 3,4-dideoxymannose (DDM) and 3,4-dideoxyglucose (DDG) from threo- and erythro-LGOL, respectively. The measured activation energies of LGOL hydrolysis are 20.5 and 23.6 kcal/mol for DDM and DDG formation, respectively. These values are in agreement with the computed protonation free energies of 17.1 and 18.2 kcal/mol, respectively. Based on the simulations, a Brønsted base-catalyzed isomerization from DDG or DDM to 3,4-dideoxy fructose (DDF) is preferred with lower apparent activation free energy barriers compared to the acid-catalyzed isomerization. In summary, this study provides mechanistic information about the conversion of the biomass-derived anhydro-sugar LGOL to 3,4-dideoxy sugars, which are precursors to renewable high-value chemicals.

Original language	English
Pages (from-to)	16339-16349
Number of pages	11
Journal	ACS Sustainable Chemistry and Engineering
Volume	8
Issue number	43
DOIs	https://doi.org/10.1021/acssuschemeng.0c06315
Publication status	Published - 2 Nov 2020

Funding

This work was conducted as part of the Computational Chemistry Physics Consortium (CCPC), which is supported by the Bioenergy Technologies Office (BETO) of Energy Efficiency & Renewable Energy (EERE). We gratefully acknowledge the computing resources provided on “BEBOP”, a computing cluster operated by the Laboratory Computing Resource Center at the Argonne National Laboratory (ANL). This research used resources of the Center for Nanoscale Materials, which was supported by the U.S. Department of Energy, Office of Science, Office of Basic Energy Sciences, under Contract DE-AC02-06CH11357. We thank the UW-Madison Department of Chemistry for use of the Bruker Avance 500 MHz NMR spectrometer. A generous gift from Paul J. Bender enabled this spectrometer to be purchased. S.H.K. acknowledges that this material is based upon work supported by the National Science Foundation under grant no. DGE-1256259. We thank the Circa Group for the supply of dihydrolevoglucosenone (Cyrene). MDB acknowledges the European Union’s Horizon 2020 research and innovation program under grant agreement no. 701028 (EU Marie Curie Global Fellowship).

UN SDGs

This output contributes to the following UN Sustainable Development Goals (SDGs)

SDG 7 Affordable and Clean Energy

Keywords

Aldose-ketose isomerization
Biomass conversion
First-principles simulation
Levoglucosanol hydrolysis
Reaction mechanism

Access to Document

10.1021/acssuschemeng.0c06315

Cite this

@article{80f4c04e0e1f4895a5f89b5bb5e06f75,

title = "Mechanistic insights into the conversion of biorenewable levoglucosanol to dideoxysugars",

abstract = "A molecular understanding of the conversion of biorenewable threo- and erythro-levoglucosanol (LGOL) to 3,4-dideoxysugars in aqueous medium is provided based on first-principles simulations. The synthetic importance of this transformation is that these intermediates can be quantitatively hydrogenated to (S,S)/(S,R) hexane-1,2,5,6-tetrol (tetrol), whose stereochemistry depends on which dideoxy sugar intermediates are formed during LGOL conversion. The thermodynamic and kinetic feasibility of the acetal (R2C(OR)2) hydrolysis in LGOL is investigated via computing the free energy profile. In aqueous medium, the rate-determining step of LGOL hydrolysis is the protonation of the anhydro-bridge oxygen atom of LGOL concurrent with ring opening, yielding the cyclic forms of 3,4-dideoxymannose (DDM) and 3,4-dideoxyglucose (DDG) from threo- and erythro-LGOL, respectively. The measured activation energies of LGOL hydrolysis are 20.5 and 23.6 kcal/mol for DDM and DDG formation, respectively. These values are in agreement with the computed protonation free energies of 17.1 and 18.2 kcal/mol, respectively. Based on the simulations, a Br{\o}nsted base-catalyzed isomerization from DDG or DDM to 3,4-dideoxy fructose (DDF) is preferred with lower apparent activation free energy barriers compared to the acid-catalyzed isomerization. In summary, this study provides mechanistic information about the conversion of the biomass-derived anhydro-sugar LGOL to 3,4-dideoxy sugars, which are precursors to renewable high-value chemicals. ",

keywords = "Aldose-ketose isomerization, Biomass conversion, First-principles simulation, Levoglucosanol hydrolysis, Reaction mechanism",

author = "Mingxia Zhou and Krishna, \{Siddarth H.\} and \{De Bruyn\}, Mario and Weckhuysen, \{Bert M.\} and Curtiss, \{Larry A.\} and Dumesic, \{James A.\} and Huber, \{George W.\} and Assary, \{Rajeev S.\}",

year = "2020",

month = nov,

day = "2",

doi = "10.1021/acssuschemeng.0c06315",

language = "English",

volume = "8",

pages = "16339--16349",

journal = "ACS Sustainable Chemistry and Engineering",

issn = "2168-0485",

publisher = "American Chemical Society",

number = "43",

}

TY - JOUR

T1 - Mechanistic insights into the conversion of biorenewable levoglucosanol to dideoxysugars

AU - Zhou, Mingxia

AU - Krishna, Siddarth H.

AU - De Bruyn, Mario

AU - Weckhuysen, Bert M.

AU - Curtiss, Larry A.

AU - Dumesic, James A.

AU - Huber, George W.

AU - Assary, Rajeev S.

PY - 2020/11/2

Y1 - 2020/11/2

N2 - A molecular understanding of the conversion of biorenewable threo- and erythro-levoglucosanol (LGOL) to 3,4-dideoxysugars in aqueous medium is provided based on first-principles simulations. The synthetic importance of this transformation is that these intermediates can be quantitatively hydrogenated to (S,S)/(S,R) hexane-1,2,5,6-tetrol (tetrol), whose stereochemistry depends on which dideoxy sugar intermediates are formed during LGOL conversion. The thermodynamic and kinetic feasibility of the acetal (R2C(OR)2) hydrolysis in LGOL is investigated via computing the free energy profile. In aqueous medium, the rate-determining step of LGOL hydrolysis is the protonation of the anhydro-bridge oxygen atom of LGOL concurrent with ring opening, yielding the cyclic forms of 3,4-dideoxymannose (DDM) and 3,4-dideoxyglucose (DDG) from threo- and erythro-LGOL, respectively. The measured activation energies of LGOL hydrolysis are 20.5 and 23.6 kcal/mol for DDM and DDG formation, respectively. These values are in agreement with the computed protonation free energies of 17.1 and 18.2 kcal/mol, respectively. Based on the simulations, a Brønsted base-catalyzed isomerization from DDG or DDM to 3,4-dideoxy fructose (DDF) is preferred with lower apparent activation free energy barriers compared to the acid-catalyzed isomerization. In summary, this study provides mechanistic information about the conversion of the biomass-derived anhydro-sugar LGOL to 3,4-dideoxy sugars, which are precursors to renewable high-value chemicals.

AB - A molecular understanding of the conversion of biorenewable threo- and erythro-levoglucosanol (LGOL) to 3,4-dideoxysugars in aqueous medium is provided based on first-principles simulations. The synthetic importance of this transformation is that these intermediates can be quantitatively hydrogenated to (S,S)/(S,R) hexane-1,2,5,6-tetrol (tetrol), whose stereochemistry depends on which dideoxy sugar intermediates are formed during LGOL conversion. The thermodynamic and kinetic feasibility of the acetal (R2C(OR)2) hydrolysis in LGOL is investigated via computing the free energy profile. In aqueous medium, the rate-determining step of LGOL hydrolysis is the protonation of the anhydro-bridge oxygen atom of LGOL concurrent with ring opening, yielding the cyclic forms of 3,4-dideoxymannose (DDM) and 3,4-dideoxyglucose (DDG) from threo- and erythro-LGOL, respectively. The measured activation energies of LGOL hydrolysis are 20.5 and 23.6 kcal/mol for DDM and DDG formation, respectively. These values are in agreement with the computed protonation free energies of 17.1 and 18.2 kcal/mol, respectively. Based on the simulations, a Brønsted base-catalyzed isomerization from DDG or DDM to 3,4-dideoxy fructose (DDF) is preferred with lower apparent activation free energy barriers compared to the acid-catalyzed isomerization. In summary, this study provides mechanistic information about the conversion of the biomass-derived anhydro-sugar LGOL to 3,4-dideoxy sugars, which are precursors to renewable high-value chemicals.

KW - Aldose-ketose isomerization

KW - Biomass conversion

KW - First-principles simulation

KW - Levoglucosanol hydrolysis

KW - Reaction mechanism

U2 - 10.1021/acssuschemeng.0c06315

DO - 10.1021/acssuschemeng.0c06315

M3 - Article

AN - SCOPUS:85095870121

SN - 2168-0485

VL - 8

SP - 16339

EP - 16349

JO - ACS Sustainable Chemistry and Engineering

JF - ACS Sustainable Chemistry and Engineering

IS - 43

ER -

Mechanistic insights into the conversion of biorenewable levoglucosanol to dideoxysugars

Abstract

Funding

UN SDGs

Keywords

Access to Document

Fingerprint

Cite this