The regioselectivity in electrophilic substitution reactions of phenol, iodine benzene, and some other analogues were studied out using density functional theory with B3LYP/6-31G(d). Positional selectivity namely o, m and p were predicted using local nucleophilic Parr functions and the Holleman rule has been examined by the Parr functions. The result obtained is in good agreement with this rule and is correctly predicted by Parr functions.
