Typical reaction: 1. The reaction of benzene with a mixture of concentrated nitric and sulphuric acids at 50oC to give nitrobenzene.
The formation of the electrophile, NO2+, is a consequence of sulphuric acid being a stronger acid than nitric acid:
HNO3 + 2H2SO4 ® NO2+ + H3O+ + 2HSO4-
Typical reaction: 2. The Friedel-Crafts reaction between chlorine and benzene in the presence of anhydrous aluminium chloride as catalyst. The reactants are heated under reflux.
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