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Problem 12

Formula: C7H9N

Spectroscopy Reference

IR spectrum NMR spectrum

Rule 3, omit the N and one H, gives C7H8
7 - 8/2 + 1 = 4 degrees of unsaturation.
Look for an aromatic ring, plus another pi bond or aliphatic ring.

The two bands at 3433 and 3354 indicate a primary amine (-NH2). The bands at 3000-2850 indicate C-H alkane stretches. The band at 3034 indicates aromatic C-H stretch; aromatics also show bands in the regions 1600-1585 and 1500-1400 (C-C in-ring stretch), and 900-675 (C-H out-of-plane). C-N stretch of aromatic amines would show up at 1335-1250 (there is a band in that region).

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 are expected to know that the ring is not para-substituted.

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