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The 1H NMR spectrum of an unknown acid has the following peaks: δ (ppm) = 12.71 (1H, s), 8.04 (2H, d), 7.30 (2H, d), 2.41 (3H, s) Which structure best fits this spectral information?

User Tjhazel
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Answer:

The most appropriate structure given the sparse spectral data is 4-acetyl benzoic acid (see attached).

Step-by-step explanation:

It is difficult to accurately elucidate the structure of this compound without its chemical formula. But from the 1H NMR spectral data shows a total of 8 hydrogen atoms:

  1. 12.71 (1H. s) - confirms presence of carboxylic acid proton, C=O-OH
  2. 8.04 (2H, d) - confirms aromatic hydrogen
  3. 7.30 (2H, d) - confirms aromatic hydrogen
  4. 2.41 (3H,s) - confirms C=C hydrogen or ketone O=C-RCH3

The attached files show the structure and the neighboring hydrogen atoms.

The most likely structure i 4-acetyl benzoic acid

The 1H NMR spectrum of an unknown acid has the following peaks: δ (ppm) = 12.71 (1H-example-1
The 1H NMR spectrum of an unknown acid has the following peaks: δ (ppm) = 12.71 (1H-example-2
User Dhinju Divakaran
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