Pseudorotaxane formation affected by stereo-electronic effects. A theoretical and experimental study

<div>A quantum chemical investigation of the stability of compounds with identical formulas was carried out on 23 classes of halogenated compounds made of H, F, Cl, Br, I, C, N, P, O and S atoms. The prevalence of formula in which its Z configuration, gauche conformation and meta isomer are the most stable forms is calculated and discussed. The prevalence data shows that in compounds made of carbon backbones, the electronic effect is weaker than the steric effect. The electronic factor is more important as the backbone atoms are replaced with atoms on the right and upper part of the periodic table.</div>

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Steric vs Electronic Effects: A New Look into Stability of Diastereomers, Conformers and Constitutional Isomers

10.26434/chemrxiv.13551182 ◽

2021 ◽

Author(s):

Sopanant Datta ◽

Taweetham Limpanuparb

Keyword(s):

Steric Effect ◽

Electronic Effect ◽

Electronic Effects ◽

Gauche Conformation ◽

Prevalence Data ◽

The Stability ◽

Stable Forms ◽

The Right ◽

Backbone Atoms ◽

Meta Isomer

<div>A quantum chemical investigation of the stability of compounds with identical formulas was carried out on 23 classes of halogenated compounds made of H, F, Cl, Br, I, C, N, P, O and S atoms. The prevalence of formula in which its Z configuration, gauche conformation and meta isomer are the most stable forms is calculated and discussed. The prevalence data shows that in compounds made of carbon backbones, the electronic effect is weaker than the steric effect. The electronic factor is more important as the backbone atoms are replaced with atoms on the right and upper part of the periodic table.</div>

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The electronic effects in and the oxygen basicity of some oxygen-containing boranes

Collection of Czechoslovak Chemical Communications ◽

10.1135/cccc19793688 ◽

1979 ◽

Vol 44 (12) ◽

pp. 3688-3694 ◽

Cited By ~ 2

Author(s):

Josef Pola ◽

Marie Jakoubková ◽

Václav Chvalovský

Keyword(s):

Hydrogen Bonds ◽

Ir Spectra ◽

Electronic Effect ◽

Electronic Effects ◽

Relative Basicity ◽

Polarizability Effect ◽

Alkoxy Groups

The oxygen relative basicity of di-n-butylboronous anhydride ((n-C4H9)2B)2O, ethyl di-n-butylboronite (n-C4H9)2BOC2H5 and some orthoborates (RO)3B having electrondonating and electronwithdrawing groups R was measured from the IR spectra of hydrogen bonds of phenol interacting with these compounds in CCl4 and analysed by means of the Taft equation. The substituent electronic effect of (n-C4H9)2B- and (RO)2B-groups attached to the oxygen of the-OR and -OB= moieties has been estimated asa more electronwithdrawing than that of structurally alike R2Z- and (RO)2Z-groups having Z = CH and SiCH3 and is discussed in terms of the vacant 2p orbital of the boron and a weak, if any, mutual polarizability effect of the alkoxy groups in orthoborates. The trimethylsiloxy group in trimethylsilyl borate possesses reduced electronwithdrawing ability compared to that in ((CH3)3SiO)3SiCH3 as a consequence of its great polarizability.

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Electronic effects of ligand substitution on metal–organic framework photocatalysts: the case study of UiO-66

Physical Chemistry Chemical Physics ◽

10.1039/c4cp04162c ◽

2015 ◽

Vol 17 (1) ◽

pp. 117-121 ◽

Cited By ~ 120

Author(s):

Lijuan Shen ◽

Ruowen Liang ◽

Mingbu Luo ◽

Fenfen Jing ◽

Ling Wu

Keyword(s):

Photocatalytic Activity ◽

Electronic Effect ◽

Metal Organic Framework ◽

Ligand Substitution ◽

Electronic Effects ◽

Metal Organic ◽

Organic Framework

The electronic effect of the ligand substituents greatly affects the photocatalytic activity of UiO-66, the rates obtained by different substituents are linearly correlated with their Hammett coefficients.

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Push or Pull for a Better Selectivity? A Study on the Electronic Effects of Substituents of the Pyridine Ring on the Enantiomeric Recognition of Chiral Pyridino-18-Crown-6 Ethers

Symmetry ◽

10.3390/sym12111795 ◽

2020 ◽

Vol 12 (11) ◽

pp. 1795

Author(s):

Balázs Szemenyei ◽

Balázs Novotny ◽

Sarolta Zsolnai ◽

Zsombor Miskolczy ◽

László Biczók ◽

...

Keyword(s):

Crown Ether ◽

Pyridine Ring ◽

Optically Active ◽

Primary Amines ◽

Titration Calorimetry ◽

Synthetic Route ◽

Electronic Effects ◽

Enantiomeric Recognition ◽

Electronic Effects Of Substituents ◽

Discriminating Ability

Seven dimethyl-substituted optically active pyridino-18-crown-6 ethers containing various substituents at position 4 of the pyridine ring were studied with regards to the electron-donating and -withdrawing effects of substituents on enantiomeric recognition. In order to compile this set of compounds, we prepared four novel pyridino-18-crown-6 ethers, including an intermediate of a new synthetic route for a formerly reported crown ether. The discriminating ability of these pyridino-crown ethers with C2-symmetry toward the enantiomers of protonated primary amines was examined by isothermal titration calorimetry.

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Structural and electronic effects involving pyridine rings in 4-methylpyridine Cu4OX6L4 complexes. I. Vibrational spectra of Cu4OBrnCl(6−n)(4-Mepy)4 complexes

Chemical Papers ◽

10.2478/s11696-008-0055-6 ◽

2008 ◽

Vol 62 (5) ◽

Author(s):

Gregor Ondrejovič ◽

Marian Koman ◽

Adela Kotočová

Keyword(s):

Pyridine Ring ◽

Symmetry Reduction ◽

Electronic Effects ◽

Vibrational Coupling ◽

Equilibrium Charge ◽

Partial Charges ◽

Gaussian Analysis ◽

Stretching Vibration ◽

Donor Acceptor ◽

Back Bonding

AbstractGaussian analysis of bands between 500 cm−1 and 600 cm−1 attributed to the $$ \tilde \nu $$ as (Cu4O) stretching vibration of the tetrahedral Cu4O core in Cu4OBrnCl(6−n)(4-Mepy)4 (n = 0–6) complexes showed two bands, symmetry reduction of the T 2 mode of vibration towards the A 1 and E modes and vibrational coupling with an R-sensitive in-plane pyridine ring bending. The Cu-O bond is considered as vibrationally coupled with the Cu-N bond and the pyridine ring through the donor-acceptor vibrational coupling and the corresponding equilibrium charge distribution. The linear correlation between $$ \tilde \nu $$ as(Cu4O) and the number of bromides in Cu4OBrnCl(6−n)(4-Mepy)4 complexes was used for the estimation of partial charges on the 4-Mepy ligands which were positive for the prevailing donors and negative for the prevailing acceptors thus evoking a π-back bonding between the Cu(II) atoms and the 4-Mepy ligands. Correlations involving selected bond lengths and bond angles in the molecular structure of the Cu4OCl6(4-Mepy)4 complex with four symmetrically independent molecules present in the unit cell indicate a symmetry reduction of the T 2 mode of vibration and the π-back bonding between the Cu(II) atoms and the 4-Mepy ligands.

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Electronic effects of heterocyclic substituents. Spectroscopical and theoretical (AM1) study in a series of heterocyclic carboxaldehydes

Canadian Journal of Chemistry ◽

10.1139/v90-226 ◽

1990 ◽

Vol 68 (9) ◽

pp. 1477-1481 ◽

Cited By ~ 13

Author(s):

C. Cativiela ◽

J. I. Garcia

Keyword(s):

Theoretical Model ◽

Electronic Effect ◽

Chemical Shifts ◽

Electronic Effects ◽

C Nmr

The electronic effects of a series of 18 heterocyclic carboxaldehydes (furans, thiophenes, pyrroles, and pyridines) have been studied by means of the correlation existing between 13C chemical shifts of the carbonylic carbon and calculated total and π charges (AM1). The implications of this theoretical model to explain polar and resonance contributions to the total electronic effect are discussed. Keywords: heterocyclic substituents, electronic effects, 13C NMR, DSP models.

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Electronic Effects in 12-Metallacrown-3 Complexes. A Theoretical and Experimental Study

Inorganic Chemistry ◽

10.1021/ic034042a ◽

2003 ◽

Vol 42 (11) ◽

pp. 3576-3581 ◽

Cited By ~ 21

Author(s):

Marie-Line Lehaire ◽

Axel Schulz ◽

Rosario Scopelliti ◽

Kay Severin

Keyword(s):

Experimental Study ◽

Electronic Effects

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