Question:
Total number of singlets observed in the $^1$H NMR of the following compound is ............
Total number of singlets observed in the $^1$H NMR of the following compound is ............
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Protons not coupled (OH, OCH\(_3\), CHO) typically appear as singlets in NMR.
Updated On: Dec 14, 2025
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Correct Answer: 3
Solution and Explanation
Step 1: Identify chemically equivalent proton groups.
The structure contains: 1. A methoxy group (OCH\(_3\)) → 3 equivalent protons → singlet.
2. An aldehyde proton (CHO) → isolated → singlet.
3. One OH proton → exchangeable → appears as a singlet.
Step 2: Check aromatic protons.
Due to substitution pattern, aromatic ring protons are not equivalent, so they will not give singlets and are ignored for this question.
Step 3: Conclusion.
Total singlets observed = 3.
The structure contains: 1. A methoxy group (OCH\(_3\)) → 3 equivalent protons → singlet.
2. An aldehyde proton (CHO) → isolated → singlet.
3. One OH proton → exchangeable → appears as a singlet.
Step 2: Check aromatic protons.
Due to substitution pattern, aromatic ring protons are not equivalent, so they will not give singlets and are ignored for this question.
Step 3: Conclusion.
Total singlets observed = 3.
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