Jump to main content
Jump to site search

Issue 7, 2003
Previous Article Next Article

Electronic properties of para-substituted thiophenols and disulfides from 13C NMR spectroscopy and ab initio calculations: relations to the Hammett parameters and atomic charges

Author affiliations

Abstract

A large number of para-substituted benzene thiols and the corresponding disulfides were synthesized and characterized by 1H NMR, 13C NMR, and IR spectroscopies. Geometries of all sixteen thiols and fourteen disulfide compounds were optimized at the B3LYP/6-31G(d) level, while the electronic structure and the 13C isotropic shifts were calculated by ab initio Hartree-Fock method coupled with the Gauge-Independent Atomic Orbital (GIAO) algorithm and a 6-31+G(d,p) basis set. The calculated 13C NMR isotropic shifts exhibit admirable agreement (δ rmsd ∼4.6 ppm) with the experimental data. The chemical shift of para-substituted carbon showed a linear correlation with Hammett constants (σp and σp+). Using this methodology the σp+ constants for the dendritic ligands have been estimated to be 0.25 and 0.24 for 2(n) and 2(o), respectively. In addition, the NBO charges on the sulfur atoms shows a latent response with the σp+ parameter. The atomic charge on the thiophenolato sulfur is invariant with the electron withdrawing ability of the substituents, however, the charge increases with increasing electron-withdrawing power.

Back to tab navigation

Supplementary files

Publication details

The article was received on 02 Jan 2003, accepted on 27 Jan 2003 and first published on 22 May 2003


Article type: Paper
DOI: 10.1039/B300048F
New J. Chem., 2003,27, 1115-1123

  •   Request permissions

    Electronic properties of para-substituted thiophenols and disulfides from 13C NMR spectroscopy and ab initio calculations: relations to the Hammett parameters and atomic charges

    R. S. Sengar, V. N. Nemykin and P. Basu, New J. Chem., 2003, 27, 1115
    DOI: 10.1039/B300048F

Search articles by author

Spotlight

Advertisements