Resumo

SANCHEZ-VIESCA, Francisco  e  BERROS, Martha. Spectroscopy and regiochemistry theory in the benzopyridines nitration. TIP [online]. 2006, vol.9, n.1, pp.19-29. ISSN 1405-888X.

In this communication we provide a theoretical explanation to the regiochemistry in the nitration of the benzopyridines as well as to the relative yields of the obtained products.

A review of the preparation procedures of the compounds under study is given, as well as the related spectroscopy. A careful study of 1 H NMR spectra revealed the existence of hydrogen bonds in these compounds. They are of the type С-Η-0-N=0, the hydrogen being at peri position to the nitro group. The existence of these bonds explains the down-field shifts observed in the signals of the involved protons.

The mass spectra of 5-nitro- and 8-nitroquinoline were determined. The fragmentation mechanisms of the typical ruptures are advanced.

Palavras-chave : Hydrogen bonds; mass spectrometry; nitroquinolines; nitroisoquinolines; nuclear magnetic resonance.

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