This chapter discusses arenes, a type of hydrocarbon. Benzene is known to be the archetypal arene as it features the original Kekulé structure with alternating double and single bonds. The electrophilic substitution reactions of benzene go in line with the high electron density above and below the benzene ring. Nitration is a particularly vital reaction undergone by benzene. This involves a nitrating mixture of concentrated nitric acid and sulfuric acid. Additionally, the electrophilic substitution of Friedel–Crafts acylation involves reagents of acyl chloride and aluminium chloride , the latter which acts as a Lewis acid. On the other hand, the electrophilic substitution of halogenation pertains to how benzene needs a catalyst for halogenation.
