DFT and neutron diffraction study of 1,6-anhydro-β-D-glucopyranose (levoglucosan)

Sládkovic̆ová, Mariana; Mach, Pavel; Smrčok, Ľubomír; Rundlöf, Håkan

doi:10.2478/s11532-006-0058-5

Cited by 11 publications

(4 citation statements)

References 27 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The chair conformation of the molecule and the axial orientation of the hydroxyl groups were chosen in accordance to the crystal structures. ,− A boat conformation would result in higher strain energy of the cyclic structure, and an equatorial orientation of the three adjacent hydroxyl groups would result in higher electrostatic repulsion between the oxygen atoms of the hydroxyl groups. The different conformations of levoglucosan, obtained by changing the direction of the hydroxyl groups, are presented in Figure .…”

Section: Resultsmentioning

confidence: 99%

Levoglucosan: A Calorimetric, Thermodynamic, Spectroscopic, and Computational Investigation

et al. 2013

View full text Add to dashboard Cite

A comprehensive analysis of the thermochemical properties of levoglucosan, using static bomb combustion calorimetry, Knudsen effusion technique, and differential scanning calorimetry, is presented. The experimental results allow us to derive the enthalpy of formation, in the gaseous phase, and thereafter to do a comparison with the same parameter obtained computationally. The good agreement between the experimental and computational results gives confidence to our determinations, particularly when they are compared with others already reported in literature. After testing the computational methodology, the ionization energy, electron affinity, proton affinity, gas-phase basicity, gas-phase acidity, and bond dissociation enthalpies of levoglucosan were also obtained. The presence of intramolecular hydrogen bonds in the most stable conformation of levoglucosan was verified by applying Quantum Theory of Atoms in Molecules calculations. Furthermore, a joint differential scanning calorimetry and temperature dynamic Fourier transform infrared (FT-IR) spectroscopic study was used to study the crystalline phase of levoglucosan between 298.15 K and the melting temperature.

show abstract

Section: Resultsmentioning

confidence: 99%

Levoglucosan: A Calorimetric, Thermodynamic, Spectroscopic, and Computational Investigation

et al. 2013

View full text Add to dashboard Cite

show abstract

“…B3LYP 47−50 has been used often in the literature to accurately predict molecular structures, 51 but in many cases, this functional underestimates the energies of transition-state structures. 52,53 M06-2X is among the best functionals for calculating barrier heights, particularly for unimolecular reactions and hydrogen atom transfer reactions.…”

Section: ■ Computational Methodsmentioning

confidence: 99%

“…B3LYP − has been used often in the literature to accurately predict molecular structures, but in many cases, this functional underestimates the energies of transition-state structures. , M06-2X is among the best functionals for calculating barrier heights, particularly for unimolecular reactions and hydrogen atom transfer reactions . M06-2X has been shown to accurately replicate results obtained using MP4(SDQ), and it has been used extensively in the literature for studying sugar chemistry .…”

Section: Methodsmentioning

confidence: 99%

Dehydration Pathways for Glucose and Cellobiose During Fast Pyrolysis

2018

View full text Add to dashboard Cite

A full understanding of all possible elementary reactions applicable to cellulose fast pyrolysis is key to developing a comprehensive kinetic model for fast pyrolysis of cellulose. Since water is an observed product of fast pyrolysis of cellulose, the energetics of the dehydration reactions of cellulose were explored computationally by using density functional theory. Glucose and cellobiose were selected as the cellulose model compounds. The four water loss mechanisms studied are Maccoll elimination, Pinacol ring contraction, cyclic Grob fragmentation, and alcohol condensation, some of which have not been considered previously in the literature. Levoglucosan formation via alcohol condensation has the lowest calculated free-energy barrier (50.4 kcal mol) for glucose dehydration. All other water loss reactions have calculated free-energy barriers greater than 60 kcal mol. Cellobiose dehydration shows similar trends to those of glucose, suggesting that these reactions are applicable to glucooligosaccharides with higher degrees of polymerization. Secondary reactions of dehydrated glucose and dehydrated cellobiose via retro-Diels-Alder and aldol rearrangement mechanisms are also explored computationally.

show abstract

“…Anhydro sugars are stable intermediates and protecting group with their extensive exploitation in carbohydrate syntheses. [1][2][3][4] They are important intermediates in synthesis of new C-nucleosides. [2,5] Because of a variety of functional groups present in their molecules, monosaccharides are of great interest for chromatography.…”

Section: Introductionmentioning

confidence: 99%

Assessment of Chromatographic Lipophilicity of Some Anhydro-D-Aldose Derivatives on Different Stationary Phases by QSRR Approach

Kоvаčеvić

Podunavac‐Kuzmanović

Jevrić

et al. 2014

Journal of Liquid Chromatography & Related Technologies

View full text Add to dashboard Cite

This study is based on the analysis of the retention behavior of some anhydro-D-aldose derivatives in reversed-phase thin-layer chromatography (RP-TLC). Chromatographic separations were achieved applying a methanol=water mobile phase and three different stationary phases: C 18 -bonded silica gel, silica gel impregnated with paraffin oil, and silica gel impregnated with squalane. Retention behavior of the analyzed molecules was defined by R 0 M constant and correlated with in silico molecular descriptors. According to the statistical validation parameters, obtained results showed that the established multiple-linear quantitative structure-retention relationship models (MLR-QSRR) can successfully predict the chromatographic lipophilicity of structurally similar compounds. In the present study the influence of some functional groups on the total lipophilicity of studied derivatives was determined as well. Principal component analysis (PCA) was applied in order to obtain an overview of similarity or dissimilarity among the analyzed compounds and hierarchical cluster analysis (HCA) was applied in order to compare separation characteristics of the applied stationary phases.

show abstract

DFT and neutron diffraction study of 1,6-anhydro-β-D-glucopyranose (levoglucosan)

Cited by 11 publications

References 27 publications

Levoglucosan: A Calorimetric, Thermodynamic, Spectroscopic, and Computational Investigation

Levoglucosan: A Calorimetric, Thermodynamic, Spectroscopic, and Computational Investigation

Dehydration Pathways for Glucose and Cellobiose During Fast Pyrolysis

Assessment of Chromatographic Lipophilicity of Some Anhydro-D-Aldose Derivatives on Different Stationary Phases by QSRR Approach

Contact Info

Product

Resources

About