Ortho, Meta and Para refer to the 1-2, 1-3, and 1-4 relationships between benzene substituents. In Electrophilic Aromatic Substitution reactions, O/M/P directing effects help us figure out where to place the incoming electrophile. Electron Donating Groups activate the ring for ortho and para addition. Electron Withdrawing Groups deactivate the ring for meta addition. Halogens are the one exception.
Electrophilic Aromatic Substitution reactions are one of the more fun topics that you will study in Organic Chemistry. But perhaps you find it tricky due to the sheer volume of information that makes up the big picture. And so, in addition to my EAS Tutorial Video Series I’ve put together a thorough EAS cheat sheet. […]