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Ring opening reaction of protonated polyfluorinated benzenes in the gas phase. A theoretical MNDO study

✍ Scribed by Jan Hrušák

Publisher
John Wiley and Sons
Year
1990
Tongue
English
Weight
453 KB
Volume
25
Category
Article
ISSN
1076-5174

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✦ Synopsis

The MNDO calculations of protonated polyfluoroknzenes [ Ph-F,] H+ indicate the possibility of a relatively free migration of the hydrogen proton with energy barriers of 125145 kJ mol-'. At a higher degree of substitution (n) the protonation of the ips0 carbon atom occupied by fluorine becomes energetically feasible, along with analogous migrations of fluorine, which, however, are energetically the most advantageous (AEm -230 kJ mol-'). In addition to bridged fluoronium ions, relatively stable cyclic intermediates were also found, which make possible a rearrangement to the difluoromethylenecyclopentadienyl cation and thus the elimination of CF, observed in collision-induced dissociation mass spectra.

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