IR/NMR data

[eldoctor]

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What are the numbers that we absolutely have to know?

 

[Prateek]

The C=O (Sharp 1800) and the OH (broad 3200-3400) shifts are definite ones to know for the IR spectrum

For NMR, I'm guessing you gotta play it by ear and do the hydrogens relative to any strong electronegative group (such as an OH). Also the carboxylic acid shift (13?) and the benzene hydrogen shift (6-8? can't recall of top of my head)

 

[BerkReviewTeach]

The C=O (Sharp 1800) and the OH (broad 3200-3400) shifts are definite ones to know for the IR spectrum

For NMR, I'm guessing you gotta play it by ear and do the hydrogens relative to any strong electronegative group (such as an OH). Also the carboxylic acid shift (13?) and the benzene hydrogen shift (6-8? can't recall of top of my head)

I second your list of key peaks. It seems all of the compounds they ever show are carbonyls or alcohols with an occassional benzene ring.

Carbonyls are closer to 1700.

Benzene Hs at 7ppm or so and alpha hydrogens in the low 2s seem to show up often.

 

[NickNaylor]

I didn't memorize the NMR spectra as the questions are usually asked in such a way that you only need to know values relatively rather than absolutely. In other words, you won't be asked what functional group corresponds to a shift of 7 ppm. Instead, you'll probably be given structures and asked which structure corresponds to the NMR data. Rote memorization usually isn't necessary.

I third the IR data: C-H saturation (~1600), all the carbonyls (aldehydes/ketones, ~1600-1900 depending on the group), and the OH stretch (broad, ~3000).