Predict the major product for the following reaction sequence. HNO3 H2SO4 NO2 NO2 NO2 NO2 Cl2 ? FeCl3
The Correct Answer and Explanation is :
The reaction sequence provided suggests a process involving nitration and halogenation reactions, specifically related to aromatic compounds. Here’s a breakdown of the steps:
- Nitration Reaction (HNO3, H2SO4):
- In the presence of concentrated nitric acid (HNO3) and sulfuric acid (H2SO4), a nitration reaction typically occurs, where a nitro group (-NO2) is introduced into an aromatic ring. This is known as an electrophilic aromatic substitution reaction.
- The nitronium ion (NO2+) generated in this reaction acts as the electrophile that attacks the aromatic ring.
- Further Nitration (NO2 NO2 NO2):
- The presence of additional NO2 groups in the reaction suggests a continued nitration process, where multiple nitro groups are introduced onto the aromatic ring.
- Typically, nitro groups are meta-directing in subsequent electrophilic substitutions. This means that the new nitro groups will be placed in the meta positions relative to any existing nitro groups.
- Halogenation (Cl2, FeCl3):
- The addition of chlorine (Cl2) and iron chloride (FeCl3) indicates a halogenation reaction, where chlorine is introduced to the aromatic ring.
- Iron chloride (FeCl3) is a Lewis acid that facilitates the generation of the electrophilic Cl+ species, which will attack the aromatic ring.
- Chlorine generally adds to the aromatic ring at positions that are ortho or para to electron-donating groups. However, nitro groups are electron-withdrawing, making them meta-directing. Thus, chlorine will add to the positions that are meta to the nitro groups.
Major Product:
The major product will be a chlorinated and nitrated aromatic compound, with the chlorine added at a position that is meta to the nitro groups.
To summarize, the reaction will yield a compound with four nitro groups and one chlorine atom, located at the meta position relative to the nitro groups. I will now generate the structure of this product.
Let me create the image for you.
The image above shows the chemical structure of the major product formed in the reaction sequence you described. It illustrates a benzene ring with four nitro groups (NO2) and one chlorine atom (Cl), where the chlorine is placed at the meta position relative to the nitro groups. This structure is based on the process involving nitration and halogenation as you outlined. Let me know if you’d like further clarification!
