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As previously mentioned, benzene does not behave like alkenes in their characteristic reactions. Instead of addition reactions, benzene undergoes substitution reactions.
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As previously mentioned, benzene does not behave like alkenes in their characteristic reactions. Instead of addition reactions, benzene undergoes substitution reactions. • Benzene is attractive to electrophiles because the ring is a region of electron density. The delocalized cloud of π electrons seeks electron-deficient species and forms a new bond as a hydrogen atom is lost. • These reactions are electrophilic substitution.
During the first step of the mechanism, an electron pair from benzene is attracted to the electrophile. This leads to a disruption of the symmetry of the ring, leading to the formation of an unstable carbocation intermediate which has both the entering atom or group and the leaving hydrogen temporarily bonded to the ring.
The loss of the hydrogen ion, H+, from the intermediate leads to the substitution product, as the two electrons from the C-H bond move to regenerate the aromatic ring.