Química Nova (Nov 2015)

RESSONÂNCIA MAGNÉTICA NUCLEAR DE SUBSTÂNCIAS ORGANOFLUORADAS: UM DESAFIO NO ENSINO DE ESPECTROSCOPIA

  • Frederico Silva Castelo Branco,
  • Bárbara V. Silva,
  • Gabriel Freitas do Rio,
  • Mábio João Santana,
  • Luiz Henrique Keng Queiroz Júnior,
  • Angelo C. Pinto,
  • Núbia Boechat,
  • Luciano Morais Lião

DOI
https://doi.org/10.5935/0100-4042.20150139
Journal volume & issue
Vol. 38, no. 9
pp. 1237 – 1246

Abstract

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Nuclear magnetic resonance is a technique that is widely used for elucidating and characterizing organic substances. Organofluorine substances have applications in many areas from drugs to liquid crystals, but their NMR spectra are often challenging due to fluoride coupling with other nuclei. For this reason, NMR spectra of this class of substances are not commonly covered in undergraduate and graduate chemistry courses and related fields. Thus, the aim of this work was the presentation and discussion of 1H, 13C, and 19F NMR spectra of eleven organofluorine substances which, in the case of 1H and 13C nuclei, showed classic patterns of first-order coupling and the effects of the fluorine nucleus in different chemical and magnetic environments. In addition, the observation of long distance coupling constants was possible through the use of apodization functions in the processing of the spectra. It is expected that the examples presented herein can be utilized and discussed in undergraduate and graduate NMR spectroscopy disciplines and thus improve the teaching and future research of organofluorine compounds.

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