Aromatic compounds have delocalised π electron cloud and behave like Lewis bases. So, electrophiles have the tendency to attack aromatic compounds and substitute H+ from the aromatic compounds. These types of reactions are called aromatic electrophilic substitution reactions like nitrosation, diazocoupling etc are responded by strongly activated aromatic rings.
In these types of reactions solvent plays an important role. For example, if halogenation. Of a very reactive aromatic compounds takes place in polar solvents, the molecular halogens alone may act as electrophiles but in non-polar solvents, halgenation is catalysed by Lewis acids like AlCl3 or SbCl5.
The increasing order of reactivity towards most of the electrophilic substitution reactions among
(i) Benzene (ii) Benzoic acid (iii) Methoxybenzene (iv) Phenyl ethanoate
a. (i) < (ii) < (iii) < (iv)
b. (i) < (ii) < (iv) < (iii)
c. (iv) < (iii) < (ii) < (i)
d. (ii) < (i) < (iv) < (iii)
