At low temperature, phenol reacts with dil. \(HNO_3\) to yield
Show Hint
- 2, 4, 6-Trinitrophenol
- o-Nitrophenol only
- p-Nitrophenol only
- ortho- and para-nitrophenol
The Correct Option is D
Solution and Explanation
The –OH group in phenol is an activating, ortho and para directing group. So electrophilic substitution like nitration goes mainly to the ortho and para positions.
Step 1:
With dilute \(HNO_3\) at low temperature, the nitration is mild, so only one –\(NO_2\) group is introduced (mononitration). Strong conditions with conc. \(HNO_3\) would be needed for trinitrophenol, so option (A) is ruled out.
Step 2:
Since –OH directs to both ortho and para, a mixture of o-nitrophenol and p-nitrophenol is formed, not just one of them.
Answer: Option (D) — phenol with dil. \(HNO_3\) at low temperature gives a mixture of ortho- and para-nitrophenol.
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