Molecular structure and reaction mechanism: A topological approach to quantum chemistry

Lignin forms an important part of lignocellulosic biomass and is an abundantly available residue. It is a potential renewable source of phenol. Liquefaction of enzymatic hydrolysis lignin as well as catalytical hydrodeoxygenation of the main intermediates in the degradation of lignin, that is, catechol and guaiacol, was studied. The cleavage of the ether bonds, which are abundant in the molecular structure of lignin, can be realised in near-critical water (573 to 673 K, 20 to 30 MPa). Hydrothermal treatment in this context provides high selectivity in respect to hydroxybenzenes, especially catechol. RANEY Nickel was found to be an adequate catalyst for hydrodeoxygenation. Although it does not influence the cleavage of ether bonds, RANEY Nickel favours the production of phenol from both lignin and catechol. The main product from hydrodeoxygenation of guaiacol with RANEY Nickel was cyclohexanol. Reaction mechanism and kinetics of the degradation of guaiacol were explored.

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Theoretical Study on Thermal Hazardous Properties of C18H10O11 and C18H18O7 Organic Peroxides

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.787.301 ◽

2013 ◽

Vol 787 ◽

pp. 301-305

Author(s):

Yun Bo He ◽

Wei Wang ◽

Shi Xiong Wang ◽

Xiang Jun Yang ◽

Hong Guo

Keyword(s):

Molecular Structure ◽

Thermal Decomposition ◽

Quantum Chemistry ◽

Organic Compounds ◽

Theoretical Study ◽

Organic Peroxides ◽

Quantum Chemistry Calculation ◽

The Past ◽

Chemistry Calculation ◽

The Stability

The thermal decomposition of organic peroxides are widely used as coagulant for organic compounds, however, its thermal hazardous characteristics have already caused serious accidents in chemical industries, which limited its application in much more strict conditions. Organic peroxides of C18H10O11 and C18H18O7 are two new candidates fitted for industrial explosive. However, as we best known there is little reports available on the geometry structure in the past decades. In this work, by means of quantum chemistry calculation, the relation of safety with molecular structure of C18H10O11 and C18H18O7 are discussed. The molecules with more activity O and the activity part more dispersedly exhibit higher stable, and the configuration has good safety. All the energy of molecule b is higher than that of molecule a. The stability of different configurations are 6a>7a>8a>9a>5a>1a>4a>3a=2a and 1b>7b>5b>6b>4b>2b>3b>8b, respectively, suggesting the structures of 6a,3a,2a,1b,8b exhibit high safety.

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Equilibrium molecular structure and spectra of 6-methyl-1,5-diazabicyclo[3.1.0]hexane: joint analysis of gas phase electron diffraction, quantum chemistry, and spectroscopic data

Physical Chemistry Chemical Physics ◽

10.1039/d0cp04005c ◽

2020 ◽

Vol 22 (39) ◽

pp. 22477-22492

Author(s):

Leonid S. Khaikin ◽

Georgiy G. Ageev ◽

Anatoliy N. Rykov ◽

Olga E. Grikina ◽

Igor F. Shishkov ◽

...

Keyword(s):

Molecular Structure ◽

Electron Diffraction ◽

Quantum Chemistry ◽

Gas Phase ◽

Vibrational Spectra ◽

Spectroscopic Data ◽

Joint Analysis ◽

Equilibrium Molecular Structure ◽

First Time ◽

Gas Phase Electron Diffraction

For the first time, the molecular structure of 6-methyl-1,5-diazabicyclo[3.1.0]hexane was determined and its NMR and vibrational spectra were studied.

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