Help me identify peaks in H NMR please

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The discussion revolves around identifying peaks in a 1H NMR spectrum related to the reduction of benzil using sodium borohydride. The experiment yielded a melting point suggesting benzoin, yet thin layer chromatography indicated a sample similar to meso-hydrobenzoin, raising concerns about purity. The user is struggling to interpret the NMR spectrum, particularly with a significant peak around 7.2 ppm that seems to indicate more hydrogens than expected for meso-hydrobenzoin. They express a preference for carbon-13 NMR over hydrogen NMR and seek assistance in verifying their findings for an upcoming lab report. The urgency of the request highlights the importance of accurate peak identification in confirming the product's identity.
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CHM238L - Identifying Peaks of H NMR spectra

Homework Statement



The experiment is "Reducing Benzil using Sodium Borohydride".
The experiment itself was simple enough and when I finished, I got a melting point of 134-136 C, which is indicative of benzoin (135-137) rather than meso-hydrobenzoin (137-139), however my thin layer chromatography revealed that my sample was nearly identical to meso-hydrobenzoin, and I tend to believe that more so than the melting point. It's possible my sample wasn't pure.

So, I also ran the NMR of my sample and got a spectra for it, but I am having trouble identifying the peaks. Please help me out here!

Here is the picture of the 1H NMR spectra.
http://img246.imageshack.us/img246/5873/95924000.jpg"

Homework Equations


This is a picture of the reaction and the 5 possible products. I circled Meso-Hydrobenzoin, which is what I believe to have after my TLC test.
http://img515.imageshack.us/img515/8025/41232169.jpg"


The Attempt at a Solution


I cleaned the NMR tube a few days in advance. I'm not sure if there is any H2O or Acetone showing in the spectra... I tried integrating the big peak at ~7.2 at 10, and I get way too many hydrogens.
It should have 14 hydrogens only if it is meso-hydrobenzoin.

Thanks in advance!
 
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Is this too difficult for people?
I'm much better at identifying the structures in Carbon 13 NMR, honestly.
I don't like hydrogen NMR.

This is for a lab report for an experiment I did last week that's due tomorrow.
I've got the rest of the lab report done, just need to verify what I have with my NMR.
Help please :p
 

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