Original scientific paper

About the Nature of Carbon-Nitrogen Triple Bond in Complexes of Nitriles with Strong Lewis Acids

Ramiz Hoti ; Faculty of Science, University of Zagreb, Chemistry Department, Strossmayerov trg 14, 41000 Zagreb, Croatia
Zlatko Mihalić ; Faculty of Science, University of Zagreb, Chemistry Department, Strossmayerov trg 14, 41000 Zagreb, Croatia
Hrvoj Vančik ; Faculty of Science, University of Zagreb, Chemistry Department, Strossmayerov trg 14, 41000 Zagreb, Croatia

Abstract

Complexes of nitriles 1-7 with antimony(V) fluoride in cryogenic matrices were studied by FT-IR spectroscopy. A large increase in C=N stretching frequency induced by complexing with SbF5 is observed in all investigated nitriles. From the vibrational changes of the nitrile molecule skeleton, it was found that the polarity of the nitrile group is increased in the complex. The inductive effect caused by complexing with SbFs was studied by observing the changes of C-CN stretching and CH3 or CH2 deformation vibrations. The qualitative similarity between vibrational changes induced either by complexing or by ionization of nitriles is discussed. Current interpretations of the nitrile effect by rehybridization of nitrogen or by partially antibonding character of the a orbital of CN bond are discussed on the basis of both the IR spectra and high level ab initio calculations.

Keywords

Hrčak ID:

136756

URI

https://hrcak.srce.hr/136756

Publication date:

1.5.1995.

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