AN MNDO STUDY OF THE ELECTROPHILIC AROMATIC-SUBSTITUTION ON TRIFLUOROBENZENES

MNDO calculations of trifluorosubstituted benzenes and their protonated intermediates [Ph-F3]H+ were performed. The results are discussed with respect to changes in geometry, charge distribution and stabilities of the individual intermediates. It appears that the predominant influence which controls the protonation position is the ability of the substituent F to increase both the positive charge and polarities of the carbon bonds situated in the meta-position with respect to the substituent, thus directing protonation to the ortho- and para-positions. © 1990 Springer-Verlag.