[hz862000]

Is there any way to tell the difference between ortho meta and para in C13 NMR?  The compound is the nitration product of methyl benzoate, and I'm pretty sure it's supposed to be meta, I just don't know how to prove it with the C13 spectrum.

[macman104]

Think about the carbons that you'll have.  If you have ortho substitution, you'll have 6 non-equivalent carbons.  If you have meta substitution, you will also have 6 non-equivalent carbons.  However, if you have para substitution, you're only going to have 4 non-equivalent carbons (draw a picture if you can't see this).

For ortho vs. meta, you're going to have to look at the pattern, and try and figure out which substitution will give you the pattern you see in your NMR.  Remember that both the ester and the nitro group are electron-withdrawing.  Use this to figure out which carbons are going to be the most deshielded/shielded.