Behaviors of hydrogen bonds formed by lignite and aromatic solvents in direct coal liquefaction: Combination analysis of density functional theory and experimental methods

The conformations of the title compounds were determined in solution (NMR and UV-Vis spectroscopy) and in the solid state (FT-IR and XRD), complemented with density functional theory (DFT) in the gas phase. The nonequivalence of the amide protons of these compounds due to the hindered rotation of the C(O)–NH2 single bond resulted in two distinct resonances of different chemical shift values in the aromatic region of their 1H-NMR spectra. Intramolecular hydrogen bonding interactions between the carbonyl oxygen and the sulfonamide hydrogen atom were observed in the solution phase and solid state. XRD confirmed the ability of the amide moiety of this class of compounds to function as a hydrogen bond acceptor to form a six-membered hydrogen bonded ring and a donor simultaneously to form intermolecular hydrogen bonded complexes of the type N–H···O=S. The distorted tetrahedral geometry of the sulfur atom resulted in a deviation of the sulfonamide moiety from co-planarity of the anthranilamide scaffold, and this geometry enabled oxygen atoms to form hydrogen bonds in higher dimensions.

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Theoretical Study on the Mechanism of Hydrogen Donation and Transfer for Hydrogen-Donor Solvents during Direct Coal Liquefaction

Catalysts ◽

10.3390/catal8120648 ◽

2018 ◽

Vol 8 (12) ◽

pp. 648 ◽

Cited By ~ 2

Author(s):

Haigang Hao ◽

Tong Chang ◽

Linxia Cui ◽

Ruiqing Sun ◽

Rui Gao

Keyword(s):

Density Functional ◽

Hydrogen Gas ◽

Hydrogen Donor ◽

Coal Liquefaction ◽

Hydrogen Atoms ◽

Functional Theory ◽

Donor Solvent ◽

National Energy Security ◽

Liquefaction Process ◽

Direct Coal Liquefaction

As a country that is poor in petroleum yet rich in coal, it is significant for China to develop direct coal liquefaction (DCL) technology to relieve the pressure from petroleum shortages to guarantee national energy security. To improve the efficiency of the direct coal liquefaction process, scientists and researchers have made great contributions to studying and developing highly efficient hydrogen donor (H-donor) solvents. Nevertheless, the details of hydrogen donation and the transfer pathways of H-donor solvents are still unclear. The present work examined hydrogen donation and transfer pathways using a model H-donor solvent, tetralin, by density functional theory (DFT) calculation. The reaction condition and state of the solvent (gas or liquid) were considered, and the specific elementary reaction routes for hydrogen donation and transfer were calculated. In the DCL process, the dominant hydrogen donation mechanism was the concerted mechanism. The sequence of tetralin donating hydrogen atoms was α-H (C1–H) > δ-H (C4–H) > β-H (C2–H) > γ-H (C3–H). Compared to methyl, it was relatively hard for benzyl to obtain the first hydrogen atom from tetralin, while it was relatively easy to obtain the second and third hydrogen atoms from tetralin. Comparatively, it was easier for coal radicals to capture hydrogen atoms from the H-donor solvent than to obtain hydrogen atoms from hydrogen gas.

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6-Bromoindigo dye

Acta Crystallographica Section C Crystal Structure Communications ◽

10.1107/s0108270112006440 ◽

2012 ◽

Vol 68 (4) ◽

pp. o160-o163 ◽

Cited By ~ 1

Author(s):

David J. Szalda ◽

Keith Ramig ◽

Olga Lavinda ◽

Zvi C. Koren ◽

Lou Massa

Keyword(s):

Density Functional Theory ◽

Quantum Theory ◽

Hydrogen Bonds ◽

Density Functional ◽

Stacking Interactions ◽

Inversion Center ◽

Asymmetric Unit ◽

Functional Theory ◽

Bond Lengths ◽

Type C

6-Bromoindigo (MBI) [systematic name: 6-bromo-2-(3-oxo-2,3-dihydro-1H-indol-2-ylidene)-2,3-dihydro-1H-indol-3-one], C16H9BrN2O2, crystallizes with one disordered molecule in the asymmetric unit about a pseudo-inversion center, as shown by the Br-atom disorder of 0.682 (3):0.318 (3). The 18 indigo ring atoms occupy two sites which are displaced by 0.34 Å from each other as a result of this packing disorder. This difference in occupancy factors results in each atom in the reported model used to represent the two disordered sites being 0.08 Å from the higher-occupancy site and 0.26 Å from the lower-occupancy site. Thus, as a result of the disorder, the C—Br bond lengths in the disordered components are 0.08 and 0.26 Å shorter than those found in 6,6′-dibromoindigo (DBI) [Süsse & Krampe (1979).Naturwissenschaften,66, 110], although the distances within the indigo ring are similar to those found in DBI. The crystals are also twinned by merohedry. Stacking interactions and hydrogen bonds are similar to those found in the structures of indigo and DBI. In MBI, an interaction of the type C—Br...C replaces the C—Br...Br interactions found in DBI. The interactions in MBI were calculated quantum mechanically using density functional theory and the quantum theory of atoms in molecules.

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Change in Energy of Intermolecular Hydrogen Bonds Upon Excitation of Coumarin 120 in Water: A Combined Time-dependent Density Functional Theory/Effective Fragment Potential Study

Communications in Computational Chemistry ◽

10.4208/cicc.2015.v3.n1.3 ◽

2015 ◽

Vol 3 (1) ◽

pp. 18-33

Author(s):

Mariyappa Ramegowda

Keyword(s):

Density Functional Theory ◽

Hydrogen Bonds ◽

Density Functional ◽

Time Dependent ◽

Intermolecular Hydrogen Bonds ◽

Functional Theory ◽

Effective Fragment Potential ◽

Potential Study ◽

Coumarin 120 ◽

Dependent Density

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IR Cavity Ringdown Spectroscopy and Density Functional Theory for Jet-Cooled Pyrrole–Cyclopentanone Binary Clusters: Effect of Pseudorotation on N—H···O═C Hydrogen Bonds

The Journal of Physical Chemistry A ◽

10.1021/acs.jpca.0c00794 ◽

2020 ◽

Vol 124 (12) ◽

pp. 2436-2448

Author(s):

Yoshiteru Matsumoto ◽

Kenji Honma

Keyword(s):

Density Functional Theory ◽

Hydrogen Bonds ◽

Density Functional ◽

Cavity Ringdown Spectroscopy ◽

Functional Theory ◽

Cavity Ringdown ◽

Binary Clusters

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Structural polymorphism of pyrazinium hydrogen sulfate: extending chemistry of the pyrazinium salts with small anions

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768110019580 ◽

2010 ◽

Vol 66 (4) ◽

pp. 451-457 ◽

Cited By ~ 4

Author(s):

Armand Budzianowski ◽

Mariana Derzsi ◽

Piotr J. Leszczyński ◽

Michał K. Cyrański ◽

Wojciech Grochala

Keyword(s):

Density Functional Theory ◽

Hydrogen Bond ◽

Dipole Moment ◽

Hydrogen Bonds ◽

Dft Calculations ◽

Density Functional ◽

Hydrogen Sulfate ◽

Structural Polymorphism ◽

Functional Theory ◽

First Time

Two polymorphs (α, β) of pyrazinium hydrogen sulfate (pyzH+HSO_4^-, abbreviated as PHS) with distinctly different hydrogen-bond types and topologies but close electronic energies have been synthesized and characterized for the first time. The α-polymorph (P212121) forms distinct blocks in which the pyzH+ and HSO_4^- ions are interconnected through a network of NH...O and OH...O hydrogen bonds. The β-form (P\bar 1) consists of infinite chains of alternating pyzH+ and HSO_4^- ions connected by NH...O and OH...N hydrogen bonds. Density functional theory (DFT) calculations indicate the possible existence of a hypothetical polar P1 form of the β-polymorph with an unusually high dipole moment.

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