Question

Label each compound as more or less reactive than benzene in electrophilic aromatic substitution.

Short answer

a. More reactive

b. More reactive

c. Less reactive

d. Less reactive

Step-by-step solution

Electrophilic aromatic substitution reaction

The electrophilic aromatic substitution reaction involves the substitution of an electrophile on the aromatic rings. The reactivity towards electrophilic-substitution depends upon the substituents on the aromatic compound.

Reactivity towards electrophilic aromatic substitution reaction

• The electron-withdrawing substituents on the aromatic ring decrease the rate of the substitution or the compound is less reactive.

• The electron-donating substituents on the aromatic ring increase the rate of the substitution reaction or the compound is more reactive.

Explanation

a. The alkyl group on the benzene is an electron-donating substituent; therefore, the compound is more reactive.

b. The OH group on the benzene is an electron-donating substituent; therefore, the compound is more reactive.

c. The\({\rm{COOC}}{{\rm{H}}_{\rm{2}}}{\rm{C}}{{\rm{H}}_{\rm{3}}}\)group on the benzene is an electron-withdrawing substituent; therefore, the compound is less reactive.

d. The \(\mathop {\rm{N}}\limits^{\rm{ + }} {\left( {{\rm{C}}{{\rm{H}}_{\rm{3}}}} \right)_{\rm{3}}}\) group on the benzene is an electron-withdrawing substituent; therefore, the compound is less reactive.