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Problem 11

Formula: C8H8O2

Spectroscopy Reference

IR spectrum NMR spectrum

Rule 2, omit O, gives C8H8
8 - 8/2 + 1 = 5 degrees of unsaturation.
Look for an aromatic ring, plus another pi bond or aliphatic ring.

The band at 1689 indicates a carbonyl, probably an acid. The broad dip at 2924 indicates the OH group of the acid. The band at 1589 indicates an aromatic ring.

Structure answer

This is the structure. See if you can assign the peaks on your own.

NMR answer

You are not expected to tell the aromatic Hs apart from each other, but you should be able to tell that the ring is not para-substituted.

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