[jmbky1]

I have a compound that is a tri-substituted benzene (1,3,5)

Two of the groups are -OR

One group is an amide bond that links the benzene to nicotinic acid (pyridine with a COOH...the COOH is "para" to the amide link)
So this group is essentially: benzene-CO-NH-nicotinic acid


My problem is in assigning the peaks or at least rationalizing them.

13.2ppm (0.56 H integration)
11.2ppm (0.73 H integration)
8.9ppm (0.85 H integration)

Normally, I'd say the 11.2 is COOH and the 8.9 is the NH. However, the obvious (and slightly broad) peak at 13.2 makes me think THAT is COOH and 11.2 is the NH. Also, the peak at 8.9 is shifted much further away from the rest of the aromatics which adds to the confusion.

The sample was run in DMSO and showed a bit of water and a tiny amount of EtOAc. Could DMSO shift an amide hydrogen all the way to 11.2?

[Polytriazole]

This is kind of weird, but I can give you at least a little info that might help.

I think you're right that the 13.2 ppm peak is the COOH proton, those tend to be pretty heavily deshielded, especially if they're a para substituent on a pyridine ring.  Your integration also makes sense, as COOH protons typically show less than quantitative integration.

It's the other two peaks that are odd.  I took at look at the chemical shifts of some common contaminants in DMSO, and sometimes the ortho proton on a pyridine ring shows up at 8.5-9 ppm.  Are you sure all of your aromatic protons are accounted for already, and the 8.9 ppm isn't simply a pyridine proton?

It's the 11.2 ppm peak that's the trickiest.  Amides don't typically show up above 9 ppm, and even urethane NH doesn't go above 8 ppm, so it's figuring out what this last trace is.  You are, however, dealing with a molecule with a high degree of aromatic content, as well as amide and carboxylic groups that could be contributing to extreme deshielding of the NH proton. 

Can you look up this compound on Web of Science or Reaxys?  Both of those databases may have links to previously reported NMR spectra of your compound that might help even if the solvent's different.

[Honclbrif]

Because DMSO is so polar, it is sometimes hard to see exchanging protons in DMSO-d₆.

Aldrich has the ¹H spectrum of nicotinamide in dueterated DMSO. From there you may have an easier time making assignments.

http://www.sigmaaldrich.com/spectra/fnmr/FNMR011121.PDF