Question & Answer

Step 1: Nucleophilic attack

• The amine lone pair (–NH₂) attacks the electrophilic carbon attached to the leaving group (Cl) in the nitrobenzyl chloride.

• Draw an arrow from the lone pair on nitrogen to the benzylic carbon.

• Simultaneously, draw an arrow from the C–Cl bond to chlorine (Cl leaves as Cl⁻).

Step 2: Formation of tetrahedral intermediate

• After the nucleophilic attack, nitrogen is positively charged (since it has 4 bonds).

• Chloride (Cl⁻) is now a free anion in solution.

• The nitro group (–NO₂) stabilizes the benzylic position through resonance.

Step 3: Proton transfer

• A proton transfer step occurs: one of the N–H hydrogens is deprotonated (either by Cl⁻ or by base present).

• Draw an arrow from the Cl⁻ (or base) to the hydrogen on nitrogen, and from the N–H bond to nitrogen.

Step 4: Final product

• You end up with a neutral secondary amine attached to the benzyl group (–CH₂–NH–).

• The leaving group is HCl.

✅ Summary of Curved Arrows You Need to Draw:

1. Lone pair on N → benzylic carbon.

2. C–Cl bond → Cl atom.

3. Cl⁻ lone pair → H of N–H.

4. N–H bond → N.