Structure, Conformational Equilibria, and Weak Hydrogen Bonding in the CH2 F2 −CF3 CH2 F Dimer

ChemPhysChem ◽  
2018 ◽  
Vol 19 (20) ◽  
pp. 2655-2661 ◽  
Author(s):  
Tao Lu ◽  
Junhua Chen ◽  
Jiaqi Zhang ◽  
Qian Gou ◽  
Zhining Xia ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Conformational Equilibria ◽  
Weak Hydrogen Bonding

scholarly journals Effects of alkanolamine solvents on the aggregation states of reactive dyes in concentrated solutions and the properties of the solutions

RSC Advances ◽  
2021 ◽  
Vol 11 (18) ◽  
pp. 10929-10934
Author(s):  
Chuangui Cao ◽  
Zhihui Zhao ◽  
Yong Qi ◽  
Hui Peng ◽  
Kuanjun Fang ◽  
...  
Keyword(s):  
Hydrogen Bonding ◽  
Steric Hindrance ◽  
Reactive Dyes ◽  
Concentrated Solutions ◽  
Weak Hydrogen Bonding ◽  
Dye Aggregation

The solvent, DEA, reduces the dye aggregation that may be caused by the weak hydrogen bonding and relatively smaller steric hindrance effect.

scholarly journals Theoretical Study of the Structures of 4-(2,3,5,6-Tetrafluoropyridyl)Diphenylphosphine Oxide and Tris(Pentafluorophenyl)Phosphine Oxide: Why Does the Crystal Structure of (Tetrafluoropyridyl)Diphenylphosphine Oxide Have Two Different P=O Bond Lengths?

Molecules ◽  
2020 ◽  
Vol 25 (12) ◽  
pp. 2778
Author(s):  
Joseph R. Lane ◽  
Graham C. Saunders
Keyword(s):  
Crystal Structure ◽  
Hydrogen Bonding ◽  
Phosphine Oxide ◽  
Density Functional ◽  
Lone Pair ◽  
Diphenylphosphine Oxide ◽  
Functional Theory ◽  
Weak Hydrogen Bonding ◽  
Independent Molecules ◽  
The Difference

The crystal structure of 4-(2,3,5,6-tetrafluoropyridyl)diphenylphosphine oxide (1) contains two independent molecules in the asymmetric unit. Although the molecules are virtually identical in all other aspects, the P=O bond distances differ by ca. 0.02 Å. In contrast, although tris(pentafluorophenyl)phosphine oxide (2) has a similar crystal structure, the P=O bond distances of the two independent molecules are identical. To investigate the reason for the difference, a density functional theory study was undertaken. Both structures comprise chains of molecules. The attraction between molecules of 1, which comprises lone pair–π, weak hydrogen bonding and C–H∙∙∙arene interactions, has energies of 70 and 71 kJ mol−1. The attraction between molecules of 2 comprises two lone pair–π interactions, and has energies of 99 and 100 kJ mol−1. There is weak hydrogen bonding between molecules of adjacent chains involving the oxygen atom of 1. For one molecule, this interaction is with a symmetry independent molecule, whereas for the other, it also occurs with a symmetry related molecule. This provides a reason for the difference in P=O distance. This interaction is not possible for 2, and so there is no difference between the P=O distances of 2.

Self-assembly of 2,6-dimethylpyridine on Cu(110) directed by weak hydrogen bonding

2007 ◽  
Vol 601 (16) ◽  
pp. L91-L94 ◽  
Author(s):  
Junseok Lee ◽  
Daniel B. Dougherty ◽  
John T. Yates
Keyword(s):  
Hydrogen Bonding ◽  
Self Assembly ◽  
Weak Hydrogen Bonding

Substitutional and solvation effects on conformational equilibria. Effects on the interaction between opposing axial oxygen atoms

1969 ◽  
Vol 47 (23) ◽  
pp. 4441-4446 ◽  
Author(s):  
R. U. Lemieux ◽  
A. A. Pavia
Keyword(s):  
Nuclear Magnetic Resonance ◽  
Hydrogen Bonding ◽  
Magnetic Resonance ◽  
Hydroxyl Groups ◽  
Evidence Based ◽  
Electrostatic Repulsion ◽  
Hydrogen Bridge ◽  
Conformational Equilibria ◽  
Free Hydroxyl ◽  
Oxygen Atoms

Evidence based both on nuclear magnetic resonance and rotation data primarily obtained from methyl 3-deoxy-β-L-erythro-pentopyranoside and a number of its derivatives is interpreted to show that the electrostatic repulsion between the oxygen atoms at the 2 and 4 positions is substantially less when these oxygens are linked to acyl groups than when in the form of either methyl ethers or as hydroxyl groups hydrogen bonded to solvent. Also, experimental evidence is presented which requires the hydrogen bridge between two axially disposed hydroxyl groups to be substantially strengthened by hydrogen bonding of the free hydroxyl by solvent.

Weak Hydrogen Bonding Can Initiate Alkane C−H Bond Activation in Acidic Zeolites

2006 ◽  
Vol 110 (42) ◽  
pp. 20762-20764 ◽  
Author(s):  
Laura S. Sremaniak ◽  
Jerry L. Whitten ◽  
Matthew J. Truitt ◽  
Jeffery L. White
Keyword(s):  
Hydrogen Bonding ◽  
Bond Activation ◽  
Weak Hydrogen Bonding ◽  
Acidic Zeolites
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