Question

Compare rate of nitration in decreasing order:

• A. A>B>C>D
• B. A>C>B
• C. B>A>C
• D. C>A>B

Hint:

Electron-donating groups (like -OMe) increase the electron density on the ring, making it more reactive towards electrophilic substitution like nitration. Conversely, electron-withdrawing groups (like -NO$_2$ and -Cl) decrease the reactivity.

Answer 1

The Correct Option is B

Step 1: Understanding the substituents.
In Ph-OMe, the -OMe group is an electron donor group, which increases electron density on the ring and facilitates nitration, so the rate of nitration is higher.
In Ph-NO$_2$, the -NO$_2$ group is a strong electron withdrawing group (-M), which reduces electron density and decreases the rate of nitration.
In Ph-Cl, -Cl is an electron withdrawing group, but not as strong as -NO$_2$, so the nitration rate is less than Ph-OMe but more than Ph-NO$_2$.
Step 2: Conclusion.
Thus, the decreasing order of nitration rate is: A>C>B, corresponding to option (2).