The old school short cut is to take the NMR and look at the shifts rather than messing about with math, electron withdrawing aryl groups deshield the aryl protons o p. the NMR also gives the overall addiitive and subtractive effect at a given position, something that the other methods struggle with, for example benzenesulfonyl guaiacol has an electron withdrawing group sulfonoxy as well as an electron donating group methoxy, which is stronger? what position does the compound undergo FC alkylation at and how readily? NMR tells you the answer in a few minutes.
The 1H NMR spectra for different substitutions on aryl compounds is easy to find and this is real world data including solvent effects, there is a rule, real chemists are real lazy, physical and theoretical chemists are alien physicists wrapped in chemist skins and they like math.
The 1H NMR spectra for different substitutions on aryl compounds is easy to find and this is real world data including solvent effects, there is a rule, real chemists are real lazy, physical and theoretical chemists are alien physicists wrapped in chemist skins and they like math.