Full multinuclear magnetic resonance analysis of 2,4-dinitrofluorobenzene

✍ Scribed by Armando Ariza-Castolo; Jorge Antonio Guerrero-Alvarez; Javier Peralta-Cruz

• Publisher: John Wiley and Sons
• Year: 2002
• Tongue: English
• Weight: 110 KB
• Volume: 41
• Category: Article
• ISSN: 0749-1581
• DOI: 10.1002/mrc.1119

✦ Synopsis

Abstract

The complete assignment of the high‐resolution NMR spectra 2,4‐dinitrofluorobenzene was made, including the ^1^H, ^13^C, ^15^N, ^17^O and ^19^F nuclei. The ^13^C,^19^F, ^13^C,^1^H, ^15^N,^19^F and ^15^N,^1^H one‐bond and long‐range coupling constants were determinated and the signs were obtained by means of two‐dimensional correlation spectroscopy: ^1^H–^1^H‐COSY, ^13^C–^1^H‐COSY, ^13^C–^1^H‐COLOC and ^1^H–^15^N, ^19^F–^15^N and ^19^F–^13^C HMQC. The spin–lattice relaxation times of ^13^C revealed their anisotropy components and it was evident that the dipole–dipole contribution of fluorine was an efficient mechanism for C‐1 relaxation. The T~1~s of ^1^H agreed with the classical description: at low temperature the main contribution is dipole–dipole relaxation and at high temperature the relaxation is dominated by the spin–rotation mechanism. A linear relationship between δ^13^C~(exp)~ and σ~C~ using GIAO (hybrid functional B3LYP) was found. ^3^J(^13^C, ^1^H) and the ^1^J(^13^C, ^13^C) have a relationship with the delocalization energies estimated by the NBO approach. Copyright © 2002 John Wiley & Sons, Ltd.