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Radicalization and Radical Catalysis of Biomass Sugars: Insights from First-principles Studies
Ab initio and density functional calculations are conducted to investigate the radicalization processes and radical catalysis of biomass sugars. Structural alterations due to radicalization generally focus on the radicalized sites, and radicalization affects H-bonds in D-fructofuranose more than in...
Autores principales: | , , , |
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Formato: | Online Artículo Texto |
Lenguaje: | English |
Publicado: |
Nature Publishing Group
2016
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Materias: | |
Acceso en línea: | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4942814/ https://www.ncbi.nlm.nih.gov/pubmed/27405843 http://dx.doi.org/10.1038/srep29711 |
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author | Yang, Gang Zhu, Chang Zou, Xianli Zhou, Lijun |
author_facet | Yang, Gang Zhu, Chang Zou, Xianli Zhou, Lijun |
author_sort | Yang, Gang |
collection | PubMed |
description | Ab initio and density functional calculations are conducted to investigate the radicalization processes and radical catalysis of biomass sugars. Structural alterations due to radicalization generally focus on the radicalized sites, and radicalization affects H-bonds in D-fructofuranose more than in D-glucopyranose, potentially with outcome of new H-bonds. Performances of different functionals and basis sets are evaluated for all radicalization processes, and enthalpy changes and Gibbs free energies for these processes are presented with high accuracy, which can be referenced for subsequent experimental and theoretical studies. It shows that radicalization can be utilized for direct transformation of biomass sugars, and for each sugar, C rather than O sites are always preferred for radicalization, thus suggesting the possibility to activate C-H bonds of biomass sugars. Radical catalysis is further combined with Brønsted acids, and it clearly states that functionalization fundamentally regulates the catalytic effects of biomass sugars. In presence of explicit water molecules, functionalization significantly affects the activation barriers and reaction energies of protonation rather than dehydration steps. Tertiary butyl and phenyl groups with large steric hindrances or hydroxyl and amino groups resulting in high stabilities for protonation products drive the protonation steps to occur facilely at ambient conditions. |
format | Online Article Text |
id | pubmed-4942814 |
institution | National Center for Biotechnology Information |
language | English |
publishDate | 2016 |
publisher | Nature Publishing Group |
record_format | MEDLINE/PubMed |
spelling | pubmed-49428142016-07-20 Radicalization and Radical Catalysis of Biomass Sugars: Insights from First-principles Studies Yang, Gang Zhu, Chang Zou, Xianli Zhou, Lijun Sci Rep Article Ab initio and density functional calculations are conducted to investigate the radicalization processes and radical catalysis of biomass sugars. Structural alterations due to radicalization generally focus on the radicalized sites, and radicalization affects H-bonds in D-fructofuranose more than in D-glucopyranose, potentially with outcome of new H-bonds. Performances of different functionals and basis sets are evaluated for all radicalization processes, and enthalpy changes and Gibbs free energies for these processes are presented with high accuracy, which can be referenced for subsequent experimental and theoretical studies. It shows that radicalization can be utilized for direct transformation of biomass sugars, and for each sugar, C rather than O sites are always preferred for radicalization, thus suggesting the possibility to activate C-H bonds of biomass sugars. Radical catalysis is further combined with Brønsted acids, and it clearly states that functionalization fundamentally regulates the catalytic effects of biomass sugars. In presence of explicit water molecules, functionalization significantly affects the activation barriers and reaction energies of protonation rather than dehydration steps. Tertiary butyl and phenyl groups with large steric hindrances or hydroxyl and amino groups resulting in high stabilities for protonation products drive the protonation steps to occur facilely at ambient conditions. Nature Publishing Group 2016-07-13 /pmc/articles/PMC4942814/ /pubmed/27405843 http://dx.doi.org/10.1038/srep29711 Text en Copyright © 2016, Macmillan Publishers Limited http://creativecommons.org/licenses/by/4.0/ This work is licensed under a Creative Commons Attribution 4.0 International License. The images or other third party material in this article are included in the article’s Creative Commons license, unless indicated otherwise in the credit line; if the material is not included under the Creative Commons license, users will need to obtain permission from the license holder to reproduce the material. To view a copy of this license, visit http://creativecommons.org/licenses/by/4.0/ |
spellingShingle | Article Yang, Gang Zhu, Chang Zou, Xianli Zhou, Lijun Radicalization and Radical Catalysis of Biomass Sugars: Insights from First-principles Studies |
title | Radicalization and Radical Catalysis of Biomass Sugars: Insights from First-principles Studies |
title_full | Radicalization and Radical Catalysis of Biomass Sugars: Insights from First-principles Studies |
title_fullStr | Radicalization and Radical Catalysis of Biomass Sugars: Insights from First-principles Studies |
title_full_unstemmed | Radicalization and Radical Catalysis of Biomass Sugars: Insights from First-principles Studies |
title_short | Radicalization and Radical Catalysis of Biomass Sugars: Insights from First-principles Studies |
title_sort | radicalization and radical catalysis of biomass sugars: insights from first-principles studies |
topic | Article |
url | https://www.ncbi.nlm.nih.gov/pmc/articles/PMC4942814/ https://www.ncbi.nlm.nih.gov/pubmed/27405843 http://dx.doi.org/10.1038/srep29711 |
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