EAS Series: Video 10
Electrophilic Aromatic Substitution gets more difficult when the starting molecule is a substituted benzene. Not only do you have to know the reaction. You also have to know how the substituent will direct the incoming electrophile, and if the substituent will slow down (deactivate) or speed up (activate) the overall reaction.
But before you can tackle directing effects, you must have a very solid understanding of the reaction intermediates, particularly the resonance stabilized sigma complex for ortho, meta and para addition reactions.
The video below takes you through the detailed resonance intermediates to help you understand this concept, and then shows you my awesome shortcut because let's face it, do you really want to draw resonance for every quiz/exam question if you don't have to?
If you find the shortcut helpful (and time-saving) please let me know by leaving a comment below.
(Watch on YouTube: Ortho/Meta/Para. Click CC on bottom right for transcript.)