Question

Account for the following: 

(i) Phenols has a smaller dipole moment than methanol 

(ii) Phenols do not give protonation reactions readily.  

Answer 1

(a). In phenol the electron withdrawing inductive effect of –OH group is opposed by electron releasing the resonance effect of –OH. 

(b). The lone pair on oxygen of –OH in phenol is being shared with benzene ring through resonance. Thus, lone pair is not fully present on oxygen and hence phenols do not undergo protonation reactions.