Benzene is a nucleophile due to its π electrons, but its reactions are slow relative to those of alkenes with the same electrophile (Br2 for example). Thus reagents for the aromatic electrophilic substitutions shown below are a combination of the source of the electrophile and a catalyst which activates the electrophile.
| forming a benzene-carbon bond | ||
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| These reactions are known as Friedel-Crafts reactions | ||
| forming a benzene-nitrogen bond | ||
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| This reaction is known as a nitration reaction. | ||