Questions: Which one of the following structures produced the following IR spectrum?

Solution Steps

• The IR spectrum shows significant peaks around 1700 cm⁻¹, 3000 cm⁻¹, and 1200 cm⁻¹.
• The peak around 1700 cm⁻¹ is indicative of a carbonyl (C=O) stretch.
• The peaks around 3000 cm⁻¹ suggest the presence of C-H stretches.
• The peak around 1200 cm⁻¹ could be due to C-O stretches.

• Option A: Contains a triple bond (C≡C), which would show a peak around 2100-2260 cm⁻¹ (not present in the spectrum).
• Option B: Contains only C-H and C-C bonds, which would not show a significant peak around 1700 cm⁻¹.
• Option C: Contains a carbonyl group (C=O), which matches the peak around 1700 cm⁻¹.
• Option D: Contains a nitrile group (C≡N), which would show a peak around 2200-2260 cm⁻¹ (not present in the spectrum).

• The spectrum shows a strong peak around 1700 cm⁻¹, which is characteristic of a carbonyl group.
• Only Option C has a carbonyl group, which matches the observed IR spectrum.

Final Answer