Last edited by Kajizil
Saturday, August 1, 2020 | History

2 edition of effect of intramolecular hydrogen bonding interactions on some conformational equilibria. found in the catalog.

effect of intramolecular hydrogen bonding interactions on some conformational equilibria.

Tauqeer A. Khan

effect of intramolecular hydrogen bonding interactions on some conformational equilibria.

by Tauqeer A. Khan

  • 383 Want to read
  • 30 Currently reading

Published by University of East Anglia in Norwich .
Written in English


Edition Notes

Thesis (Ph.D.), University of East Anglia, School of Chemical Sciences, 1984.

ID Numbers
Open LibraryOL14502888M

O-H bond, the positive end of which is hydrogen. hydrogen has a very low electronegitivity so it bonds with one with a high electronegitivity such as F, O or N. -weaker bond then covalent -molecule contains a highly polar bond, such as O-H nond. the positive end is H interacts easily with other unshared electrons.   The hydrogen bond strength, molecular geometry, π-electron delocalization, and physical properties such as dipole moment, chemical potential, and chemical hardness of 4-nitropyridinethiol and its 29 derivatives have been studied by means of density functional method with ++G** basis set in gas phase and water solution. Also, the excited-state properties of intramolecular hydrogen Cited by: 9.

  a) is misguided, H bonding is an attractive stress between the lone pair of an electronegative atom (N, O, F) and a hydrogen atom it incredibly is hooked up directly to N, O or F. b) fake; butane is way less soluble than methanol c) fake; hydrogen bonding is the rationalization in the back of the extreme solubility of sugar and alcohol in water. pected to be major contributors to the conformational equilibria of the acetates (R = Ac), whereas in the hydroxy compounds (R = R) the rotational distribu­ tion could be altered significantly as a result of intra­ molecular hydrogen bonding. In theory each of the diastereomers .

An intramolecular force is any force that binds together the atoms making up a molecule or compound, not to be confused with intermolecular forces, which are the forces present between molecules. The subtle difference in the name comes from the Latin roots of English with inter meaning between or among and intra meaning inside. Chemical bonds are considered to be intramolecular forces, for. - TC between and ppb K-1 is considered a weak intramolecular hydrogen bonds, - TC between and ppb K-1 there are no intramolecular hydrogen bonds present. - For TC more negative than ppb K-1 the environment in which the measured proton sits is subject to large conformational changes when temperature is changed, and.


Share this book
You might also like
Principles of industrial psychology.

Principles of industrial psychology.

The united negro: his problems and his progress

The united negro: his problems and his progress

The Teenage Edge

The Teenage Edge

Wicked environmental problems

Wicked environmental problems

International buyers exhibitions under the small and medium-sized enterprises community initiative

International buyers exhibitions under the small and medium-sized enterprises community initiative

technique of making leaded glass ornaments

technique of making leaded glass ornaments

lake

lake

In Search of the Liberty Tree

In Search of the Liberty Tree

Elementary computer curriculum guide

Elementary computer curriculum guide

Somewhat close to normal

Somewhat close to normal

The antiphon

The antiphon

Effect of intramolecular hydrogen bonding interactions on some conformational equilibria by Tauqeer A. Khan Download PDF EPUB FB2

1. Introduction. Conformational preferences can cause non-contiguous atoms within an isolated molecule to become similarly close neighbors.

These spatial arrangements may be driven by favorable electrostatic interactions or by the special case where three of such atoms form a so-called “hydrogen bond” (H-bond).Cited by: $\begingroup$ With intramolecular hydrogen bonding, the substance would generally be less soluble in water and would thus require a higher T for dissolution.

This is because the molecules are not as able to interact with the solvent water molecules, via H bonding, as their polar functional groups are involved in an intramolecular interaction.

A hydrogen bond (often informally abbreviated H-bond) is a partial intermolecular bonding interaction between a lone pair on an electron rich donor atom, particularly the second-row elements nitrogen (N), oxygen (O), or fluorine (F), and the antibonding molecular orbital of a bond between hydrogen (H) and a more electronegative atom or group.

Such an interacting system is generally denoted Dn. The lack of intramolecular hydrogen bonding and the side chain effect in alanine conformers Article in Journal of Molecular Structure April with 60 Reads How we measure 'reads'.

The balance between intra- and intermolecular hydrogen bonding is studied for a solution of methyl β-cellobioside in water and dimethylsulfoxide by 1 H NMR and molecular dynamics simulations. In water O(3) predominantly interacts with water molecules, whereas in dimethylsulfoxide it is intramolecularly hydrogen bonded to O(5′).Cited by: Intramolecular interactions too can be studied; for example, Kuhn and co-workers published a seminal review of intramolecular hydrogen bonding for medicinal chemists based (in part) on.

Hydrogen bonding is a really interesting phenomenon. It can drastically change the physical properties of any substances.

As you might know, hydrogen bonding is a bond between hydrogen, which is a highly electropositive element and a highly elec. intermolecular bonding - hydrogen bonds This page explains the origin of hydrogen bonding - a relatively strong form of intermolecular attraction.

If you are also interested in the other intermolecular forces (van der Waals dispersion forces and dipole-dipole interactions), there is a link at the bottom of the page. This review is mainly focused on the intramolecular HB hence hydrogen bonding is highlighted in the scheme.

The change in molecular interactions are reflected in physical, chemical and biological phenomenon, such as, phase transitions of water (ice to water to vapor or vice versa), protein folding and unfolding and separation of DNA strands Cited by: A majority of the presented studies covers the phenomena of proton transfer (PT), steric effect, quasi-aromatic hydrogen bonding, aromaticity, tautomeric and conformational equilibria.

It should be stressed that the studies of the proton transfer process are of great importance in the description of some enzymatic reactions activated by the Cited by: Ab initio and density functional theory (DFT) calculations on some model systems are presented to assess the extent to which intermolecular hydrogen bonding can affect the planarity of amide groups.

Formamide and urea are examined as archetypes of planar and non-planar amides, optimisations suggest that appropriately disposed hydrogen-bond donor or acceptor molecules can.

The hydroxyl group may be hydrogen bonded to a number of atoms with lone pair electrons, as well as to other electron- donating centers, and the interaction may be inter- or intramolecular. Examples of the effect of intermolecular hydrogen bonding are the high boiling point of ethanol and the large differences in reactivity of heterolytic Cited by: 8.

Some model compounds for intramolecular hydrogen bonding are presented. Giga-fren The conformation about the glycosyl bond is anti, the furanose ring adopts a C3′ endo/C4′ exo pucker and the conformation of the side chain is gauche+, stabilized by an intramolecular hydrogen bond.

Solvent and substituent effects on the conformational equilibria and intramolecular hydrogen bonding of 4-substitutedhydroxybenzaldehydes Sonia E. Blanco, Ferdinando H. Ferretti Tetrahedron Letters 48 (14), Cited by: This book gives an extensive description of the state-of-the-art in research on excited-state hydrogen bonding and hydrogen transfer in recent years.

Initial chapters present both the experimental and theoretical investigations on the excited-state hydrogen bonding structures and dynamics of many organic and biological chromophores. Intermolecular and Intramolecular Bonding study guide by SarinaWolfe includes 9 questions covering vocabulary, terms and more.

Quizlet flashcards, activities and games help you improve your grades. Water is a polar molecule, and its intramolecular bonds are polar covalent. to place it basically, the bonding is covalent, and not ionic, by fact the two hydrogen and oxygen are nonmetals (at known temperature and rigidity).

it particularly is a polar molecule by fact of its molecular shape and due to the disparity interior the. I don't think there is much of a difference between the strengths of intramolecular or intermolecular hydrogen bonds.

However the strength of interactions between molecules depends on the type of hydrogen bond. Consider a typical example: ortho-Nitrophenol has a lower melting and boiling point than para-Nitrophenol. intramolecular hydrogen bond (a hydrogen bond formed between two functional groups of the same molecule) cyclization of ω-haloalkylamines and alcohols to form the corresponding saturated nitrogen and oxygen heterocycles, respectively (an S N 2 reaction within the same molecule).

Effect of intermolecular hydrogen bonding is as follows I don't understand one point i.e how occurrence of liquid state is associated with intermolecular hydrogen bonding as intermolecular hydrogen bonding helps in closed packing of molecules it should give rise to solid state.

The combined utility of many one and two dimensional NMR methodologies and DFT-based theoretical calculations have been exploited to detect the intramolecular hydrogen bond (HB) in number of different organic fluorine-containing derivatives of molecules, viz.

benzanilides, hydrazides, imides, benzamides, and diphenyloxamides. The existence of two and three centered hydrogen bonds has been Cited by: Effect of intermolecular hydrogen bonding and proton transfer on fluorescence of salicylic acid’ G.S. Denisov*, N.S.

Golubev, V.M. Schreiber, Sh.S. Shajakhmedov, A.V. Shurukhina Effects of intermolecular interactions, in particular the influence of intermolecular hydrogen bonds formed by salicylic acid intramolecular hydrogen bond. Intramolecular H-bonds would not prevent a molecule from participating in intermolecular H-bonding.

Intramolecular H-bonds would, however, stabilize the molecule, and would affect things such as its heat of combustion or heat of formation.