Question

why phenols do not react with thionyl chloride?

Answer 1

Reaction with SOCl2 generally follows, SN​2mechanism, wherein there is simultaneous formation and breaking of the bonds. But, in case of phenol the the carbon attached to the phenolic OH is sp2 hybridised and an hence the SN2 type of attack is not possible. Moreover, the attack at the carbon will disrupt the aromatic stabilization of the ring as well. Hence, phenols do no react with SOCl2.