Three centered hydrogen bonds of the type CO⋯H(N)⋯X–C in diphenyloxamide derivatives involving halogens and a rotating CF<sub>3</sub>group: NMR, QTAIM, NCI and NBO studies

Lakshmipriya, A.; Chaudhari, Sachin Rama; Shahi, Abhishek; Arunan, E.; Suryaprakash, N.

doi:10.1039/c4cp05917d

Cited by 17 publications

(25 citation statements)

References 44 publications

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“…Initial studies were focused on the concentration dependence of NH chemical shift (δ NH ) for all the molecules and it was observed that δ NH remained unaltered for all the molecules, discarding the presence of any type of intermolecular interactions [ 166 ]. Compared to the unsubstituted molecule 33 the chemical shifts of NH protons are observed to be more deshielded for the different substituted molecules, 34 – 38 , indicating the participation of NH proton in weak molecular interactions [ 166 ]. The deshielding of NH chemical shift on lowering the temperature due to the strengthening in the HB is evident from Figure 34 A.…”

Section: Studies On Diphenyloxamidesmentioning

confidence: 99%

Intramolecular Hydrogen Bonding Involving Organic Fluorine: NMR Investigations Corroborated by DFT-Based Theoretical Calculations

Mishra

Suryaprakash

2017

Molecules

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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 convincingly established in the investigated molecules. The NMR spectral parameters, viz., coupling mediated through hydrogen bond, one-bond NH scalar couplings, physical parameter dependent variation of chemical shifts of NH protons have paved the way for understanding the presence of hydrogen bond involving organic fluorine in all the investigated molecules. The experimental NMR findings are further corroborated by DFT-based theoretical calculations including NCI, QTAIM, MD simulations and NBO analysis. The monitoring of H/D exchange with NMR spectroscopy established the effect of intramolecular HB and the influence of electronegativity of various substituents on the chemical kinetics in the number of organic building blocks. The utility of DQ-SQ technique in determining the information about HB in various fluorine substituted molecules has been convincingly established.

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Section: Studies On Diphenyloxamidesmentioning

confidence: 99%

Intramolecular Hydrogen Bonding Involving Organic Fluorine: NMR Investigations Corroborated by DFT-Based Theoretical Calculations

Mishra

Suryaprakash

2017

Molecules

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“…45 The phenylacetylene-H 2 O complex has a nearly planar geometry in which both molecules simul- Another comprehensive study on diphenlyoxamide derivatives used NMR spectroscopy, AIM and NCI analyses on intramolecular hydrogen bonds. 46 The structure of diphenyloxamide is shown in Figure 4 and it has the potential for three intramolecular hydrogen bonds. The three 'hydrogen bond angles' for the various derivatives are given in Table 2.…”

Section: Hf Hcl Hbr Hnc Hcn Hcchmentioning

confidence: 99%

Why are Hydrogen Bonds Directional?

Shahi

Arunan

2016

J Chem Sci

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The recent IUPAC recommendation on the definition of hydrogen bonding points out that directionality is a defining characteristic of a hydrogen bond and the angle ∠X-H-Y is generally linear or 180 •. It also suggests that the X-H• • • Y angle be greater than 110 • for an interaction to be characterized as a hydrogen bond but does not provide any rationale for the same. This article reports a rationale for limiting the angle, based on the electron density topology using the quantum theory of atoms in molecules. Electron density topology for common hydrogen bond donors HF, HCl, HBr, HNC, HCN and HCCH are reported in this work. These calculations lead to an interesting observation that the atomic basins of H atom in all these donor molecules are limited justifying the restriction of hydrogen bond angle. Moreover, similar analysis on some hydrogen bonded complexes confirms that beyond this angle the acceptor atom Y starts interacting with the atomic basin on X. However, conclusions based on bond lengths and angles have to be treated with care and as the IUPAC recommendation points out that independent 'evidence for bond formation' in every case is important.

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“…We found that the NBO analysis did not show any specific overlap corresponding to these BCPs. 51 In the figure 6, sign(2)* is plotted as function 1 on x-axis and its negative values imply attractive interaction (hydrogen bond, halogen bond or van der Waals interaction) whereas positive values imply repulsive interaction (steric effect). This method is able to determine the very weak intramolecular interaction in 1,2-ethanediol which is not identified through BCP.…”

Section: Nci Analysismentioning

confidence: 99%

Microwave spectroscopic and theoretical investigations of the strongly hydrogen bonded hexafluoroisopropanol⋯water complex

Shahi

Arunan

2015

Phys. Chem. Chem. Phys.

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This paper reports microwave spectroscopic and theoretical investigations on the interaction of water with hexafluoroisopropanol (HFIP). The HFIP monomer can exist in two conformations, antiperiplanar (AP) and synclinical (SC). The former is about 5 kJ mol(-1) more stable than the latter. Theoretical calculations predicted three potential minima for the complex, two having AP and one having SC conformations. Though, the binding energy for the HFIP(SC)···H2O turned out to be larger than that for the other two conformers having HFIP in the AP form, the global minimum for the complex in the potential energy hypersurface had HFIP in the AP form. Experimental rotational constants for four isotopologues measured using a pulsed nozzle Fourier transform microwave spectrometer, correspond to the global minimum in the potential energy hypersurface. The structural parameters and the internal dynamics of the complex could be determined from the rotational spectra of the four isotopologues. The global minimum has the HFIP(AP) as a hydrogen bond donor forming a strong hydrogen bond with H2O. To characterize the strength of the bonding and to probe the other interactions within the complex, atoms in molecules, non-covalent interaction index and natural bond orbital theoretical analyses have been performed.

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Three centered hydrogen bonds of the type CO⋯H(N)⋯X–C in diphenyloxamide derivatives involving halogens and a rotating CF₃group: NMR, QTAIM, NCI and NBO studies

Cited by 17 publications

References 44 publications

Intramolecular Hydrogen Bonding Involving Organic Fluorine: NMR Investigations Corroborated by DFT-Based Theoretical Calculations

Intramolecular Hydrogen Bonding Involving Organic Fluorine: NMR Investigations Corroborated by DFT-Based Theoretical Calculations

Why are Hydrogen Bonds Directional?

Microwave spectroscopic and theoretical investigations of the strongly hydrogen bonded hexafluoroisopropanol⋯water complex

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Three centered hydrogen bonds of the type CO⋯H(N)⋯X–C in diphenyloxamide derivatives involving halogens and a rotating CF3group: NMR, QTAIM, NCI and NBO studies

Cited by 17 publications

References 44 publications

Intramolecular Hydrogen Bonding Involving Organic Fluorine: NMR Investigations Corroborated by DFT-Based Theoretical Calculations

Intramolecular Hydrogen Bonding Involving Organic Fluorine: NMR Investigations Corroborated by DFT-Based Theoretical Calculations

Why are Hydrogen Bonds Directional?

Microwave spectroscopic and theoretical investigations of the strongly hydrogen bonded hexafluoroisopropanol⋯water complex

Contact Info

Product

Resources

About

Three centered hydrogen bonds of the type CO⋯H(N)⋯X–C in diphenyloxamide derivatives involving halogens and a rotating CF₃group: NMR, QTAIM, NCI and NBO studies