Phenols undergo electrophilic substitution reactions readily due to the strong
activating effect of the OH group attached to the benzene ring. Since the OH group
increases the electron density more to the ortho- and para- positions, one of the
examples of the aldehyde group being introduced on the aromatic ring of phenol, ortho
to the hydroxyl group. This is a general method used for the ortho-formylation of
phenols.
Answer the following questions: