Certainly! The preparation of 2,4-dinitrophenol from phenol and nitric acid involves a nitration reaction. The reaction mechanism can be divided into three main steps: protonation of nitric acid, electrophilic substitution, and deprotonation. Here's a detailed explanation of the reaction mechanism:1. Protonation of nitric acid:Nitric acid HNO is a strong acid, and it can donate a proton H to the phenol CHOH molecule. This protonation step activates the phenol by converting the hydroxyl group -OH into a better leaving group -OH . The protonated phenol is now ready to undergo electrophilic substitution.2. Electrophilic substitution:The first nitration occurs when the nitronium ion NO , which is formed from the protonated nitric acid, attacks the phenol molecule at the ortho or para position. The ortho and para positions are more reactive due to the electron-donating effect of the hydroxyl group, which increases the electron density at these positions. The attack of the nitronium ion results in the formation of a resonance-stabilized carbocation intermediate.In the case of 2,4-dinitrophenol, the first nitration occurs at the para position, forming a 4-nitrophenol intermediate. This intermediate is more reactive than the starting phenol due to the presence of the nitro group -NO , which is a strong electron-withdrawing group. This increases the reactivity of the ortho position relative to the para position, facilitating the second nitration.The second nitration occurs when another nitronium ion attacks the 4-nitrophenol intermediate at the ortho position, forming a resonance-stabilized carbocation intermediate. This leads to the formation of 2,4-dinitrophenol.3. Deprotonation:The final step in the reaction mechanism is the deprotonation of the 2,4-dinitrophenol molecule. A water molecule HO acts as a base and abstracts a proton from the hydroxyl group -OH to regenerate the hydroxyl group -OH and form 2,4-dinitrophenol.Overall, the reaction mechanism involves the protonation of nitric acid, electrophilic substitution at the ortho and para positions, and deprotonation to form 2,4-dinitrophenol. The key intermediates involved in this reaction are the protonated phenol, the resonance-stabilized carbocation intermediates, and the 4-nitrophenol intermediate.