The reaction of platinum(II) derivatives of polycyclic aromatic hydrocarbons (PAHs) with bromine followed by irradiation with light gives selectively aromatic ring brominated products via preceding platinum(IV) intermediates. Previously, a series of organometallic compounds with platinum at the edge has been prepared by oxidative addition reactions. The reaction of bromocorannulene, 9-bromophenanthrene and 1-bromonaphthalene with Pt(PEt₃)₄ affords trans-L₂PtRBr. (L=PEt₃, R = corannulenyl, phenanthrenyl and naphthalenyl) Addition of bromine to the corresponding platinum(II) complexes in carbontetrachloride generates six coordinated platinum(IV) complexes, trans-L₂PtRBr₃. In the presence of light, the neighboring carbon to platinum metal center on the aromatic ring is regioseletively brominated with conversion to platinum(II) complexes, trans-L₂PtR`Br along with HBr. (R`= bromocorannulenyl, bromophenanthrenyl and bromonaphthalenyl)