Why is there a peak at 3300 for pyridine IR?

[IDreamtIChased]

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Is it a mistake? There's also a peak at 2947 and 1437 - I'm guessing that's the C-H and the C-N.

Any help appreciated.

 

[DougTPR]

Is it a mistake? There's also a peak at 2947 and 1437 - I'm guessing that's the C-H and the C-N.

Any help appreciated.

Is this what your spectrum looks like?

http://webbook.nist.gov/cgi/cbook.cgi?ID=C110861&Units=SI&Type=IR-SPEC&Index=3#IR-SPEC

Not all C-H's in this molecule are created equal this more than one C-H signal. It could also be an artifact of the technique used to produce the spectrum. If your peak at 3300 is broad, there is likely water in the sample.

The trick with IR is not to read too much into each and every signal. In general, MCAT IR revolves around two signals: C=O and O-H.

 

[Halfling]

Is it a mistake? There's also a peak at 2947 and 1437 - I'm guessing that's the C-H and the C-N.

Any help appreciated.

My guess:

Peak around 1437 are probably C=C (C-C are in the fingerprint area)
Peak around 2947 are probably H-C-N and H-C-C
Peak around 3300 are probably H-C=N and H-C=C (although 3300 is pretty high, but it may just be cause of the Nitrogen in the ring).

The IR provided above shows a few peaks in those regions, so that's why I have a few groups for the values.