𝔖 Bobbio Scriptorium
✦   LIBER   ✦

NMR study of substituent effects in 4-substituted and 4,4′-disubstituted diphenyl sulphides

✍ Scribed by R. Chandrasekaran; S. Perumal; D. A. Wilson


Publisher
John Wiley and Sons
Year
1987
Tongue
English
Weight
470 KB
Volume
25
Category
Article
ISSN
0749-1581

No coin nor oath required. For personal study only.

✦ Synopsis


The proton and carbon NMR spectra of nine 4-X-diphenyl sulphides (series l), seven 4-X-4'-N02-diphenyl sulphides (series 2) and eight 4,4'-X2-diphenyl sulphides (series 3) have been obtained. Correlation of the I3C chemical shifts with the appropriate substituent chemical shifts (SCS) for monosubstituted benzenes (Lynch plots) show an enhancement of substituent effect at C-1 (carbon para to the substituent) in series 1 and 2, but not in series 3. The carbons of the unsubstituted ring in series 1 also correlate with C,-SCS, with slopes of less than unity; correlation for C-1' has a negative slope. Dual substituent parameter (DSP) correlations of the 13C chemical shifts with u,/u$ are good to excellent for all the carbons of series 1 compounds, except those ortho to the substituent X. The carbons meta to the substituent X correlate well, but with negative values for pI and pR, although showing a scattered Lynch plot. Similar correlations are found with some carbon shifts in series 2, and with C-1 shifts in series 3.

It is concluded that (a) reverse resonance effects are operative at the position meta to the variable substituent by virtue of the sulphur substituent ortho to that carbon; (b) there is transmission of inductive (field) and resonance effects from one aryl ring to the other, except when both rings carry substituents of the same electronic character (series 3); (c) there is some evidence for m-polarization in the unsubstituted phenyl ring of series 1 compounds.


📜 SIMILAR VOLUMES


77Se n.m.r. studies of organoselenium co
✍ S. Gronowitz; A. Konar; A.-B. Hörnfeldt 📂 Article 📅 1977 🏛 John Wiley and Sons 🌐 English ⚖ 460 KB

## Abstract ^77^Se N.m.r. spectra of 4,4′‐disubstituted diphenyl selenides have been obtained. The chemical shifts could be correlated with substituent constants of the Hammett type or with Swain and Lupton two‐parameter equations. No correlations were observed between these ^77^Se shifts and the ^

A proton and carbon NMR spectral study o
✍ Alan R. Katritzky; S. Perumal 📂 Article 📅 1990 🏛 John Wiley and Sons 🌐 English ⚖ 301 KB

## Abstract The proton and carbon NMR spectra of several 4‐substituted‐ and 4,6‐disubstituted‐dibenzothiophenes have been measured, and their chemical shifts assigned employing spin decoupling and COSY and HETCOR two‐dimensional techniques. This work rectifies several literature misassignments of ^

1H, 13C and 17O NMR study of substituent
✍ Subbu Perumal; Gnanasambandam Vasuki; Veerappan Vijayabaskar; Sangavanaicker Sel 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 200 KB 👁 1 views

The 1H and 13C NMR spectra of 4-substituted phenylthiol acetates, benzoates and cinnamates and the 17O NMR spectra of a few thiol acetates were measured. The 13C chemical shifts of C-1 of the thiol esters when correlated with appropriate substituent-induced chemical shifts (SCS) of monosubstituted b

17O NMR spectroscopy of 4-substituted py
✍ D. W. Boykin; A. L. Baumstark; P. Balakrishnan 📂 Article 📅 1985 🏛 John Wiley and Sons 🌐 English ⚖ 309 KB

## Abstract The ^17^O chemical shifts for 4‐substituted pyridine __N__‐oxides at natural abundance were measured in acetonitrile at 50°C. Electron withdrawing groups caused deshielding and electron donating groups caused shielding of the ^17^O resonance. The data are correlated with ^17^O chemical

Stereodynamics of 4-substituted cyclohex
✍ Rosalyn V. Concepcion; James J. Breeyear; John G. Jewett; C. Hackett Bushweller 📂 Article 📅 1998 🏛 John Wiley and Sons 🌐 English ⚖ 157 KB

The 1 H and 13 C{ 1 H} NMR spectra of 4-formylcyclohexene in 50% CF 2 Cl 2 -50% CHF 2 Cl decoalesce at very low temperatures and, at 108 K, have sharpened into a major (77%) and a minor (23%) subspectrum. Based on the NMR spectra and molecular mechanics calculations, the major subspectrum is assigne