Which one of the following compounds will be most readily
attacked by an electrophile ?
(a) Chlorobenzene (b) Benzene
(c) Phenol (d) Toluene
Answers
Which one of the following compounds will be most readily
attacked by an electrophile ?
(a) Chlorobenzene
(b) Benzene
(c) Phenol
(d) Toluene
Compound which would be most readily attacked by an electrophile is :
a) Chlorobenzene ( C₆H₅Cl )
• Presence of deactivating group like chlorine, decrease electron density on benzene making it less favorable for electrophilic substitution.
b) Benzene ( C₆H₆ )
• It favor electrophilic substitution, as it is electron rich and attracts electrophile.
c) Phenol ( C₆H₅OH )
• Donation of the oxygen's lone pair into the ring system increases the electron density around the ring ( +M effect ). And increases rate for electrophilic substitution.
d) Toluene ( C₆H₅CH₃ )
• The CH₃ group attached to the benzene ring increases the electron density through ( + H and +I effect ).
• Resonance effects are generally far more superior as compared to hyperconjugation.
• Hence phenol would be most readily attacked by an electrophile.