Dynamic ¹H NMR studies of hindered internal rotations in the synthesized particular phosphorus ylide: experimental and theoretical approaches

Sayyed Mostafa Habibi-Khorassani; Mehdi Shahraki; Malek Taher Maghsoodlou; Susan Erfani

doi:10.1016/j.saa.2015.02.084

Dynamic ¹H NMR studies of hindered internal rotations in the synthesized particular phosphorus ylide: experimental and theoretical approaches

Spectrochim Acta A Mol Biomol Spectrosc. 2015 Jun 15:145:410-416. doi: 10.1016/j.saa.2015.02.084. Epub 2015 Mar 9.

Authors

Sayyed Mostafa Habibi-Khorassani¹, Mehdi Shahraki², Malek Taher Maghsoodlou², Susan Erfani²

Affiliations

¹ Department of Chemistry, University of Sistan and Baluchestan, P.O. Box 98135-674, Zahedan, Iran. Electronic address: smhabibi@chem.usb.ac.ir.
² Department of Chemistry, University of Sistan and Baluchestan, P.O. Box 98135-674, Zahedan, Iran.

PMID: 25796011
DOI: 10.1016/j.saa.2015.02.084

Abstract

Dynamic (1)H NMR measurements were performed within the synthesized particular phosphorus ylide involving 4-formylphenyl phenylcarbamate. Four rotational process and thereby parameters were targeted for rotation around the CC, C-C, HCNC and OCNC bonds. The Gibbs free activation energy in CDCl3, ΔG(≠)exp, was found to be 64 ± 2, 50 ± 2, 41 ± 2 and 63 ± 2, respectively. These findings were compared with related ab initio and DFT results on simulated situation. Theoretical methods tested, were comparable to the present D (1)H NMR data.

Keywords: Ab initio; D (1)H NMR; DFT; Rotational barrier; Ylide.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Isomerism
Models, Theoretical*
Phosphorus / chemistry*
Proton Magnetic Resonance Spectroscopy*
Rotation*
Thermodynamics

Substances

Phosphorus