[jjblt]

Hello,

I have been racking my brain all week trying to figure out my unknown.  I believe it is an ester or ketone, but I can't determine exactly which compound it is. 

-White solid. Melting point 72.0 degrees celsius
-Soluble in ether, concentrated H2SO4
-Insoluble in water, NaOH, Sat. NaHCO3, 10% HCl,

-Chemical tests came back negative for an alcohol, as did IR analysis.
Sodium Fusion test came back negative for Nitrogen and for Halogens (though it seems like halogen test is real particular and negative results can easily occur if you make the simplest mistake).

-The aluminum chloride/chloroform test for arenes for came back negative.  I know it is an aromatic ring for a fact, so it must have a pi or sigma electron withdrawing group attached to it because those would give negative results. 

-The proton NMR showed a group of multiplets between 7 and 8 and one very, very tiny peak at 1.705 which I wonder if this is an impurity. 

Here are the important peaks on my IR. I definitely think it's an aromatic ring, but I don't know if the other peaks are ester peaks or not?  There's just a mess of peaks from 1500 to 600.

3062.8 -- very small peak. CH of aromatic ring?
2926.5 -- very small peak. alkyl CH.

1710.5 -- small to moderate. this peak confuses me.  I've never had a peak of this size show up in this location.  It doesn't seem big enough to be a carbonyl or small enough to be aromatic overtones. 

1648.5 -- 4th largest absorption in the IR.  I assume it's a conjugated C=O. Seems too low to be an ester, so I'm thinking ketone.

1595.7, 1578.1 -- seems like a doublet.  The peak at 1578.1 is 2/3rd the size of the peak at 1648.
1482.9 -- moderate
1444.3 -- moderate
1400.0 -- moderate
1375.2 -- small
1317.7 -- small to moderate
1299.3 -- moderate
1277.6, 1247.5 -- show up as a doublet
1087 -- 5th largest absorption
843.2 -- 3rd largest absorption
788.7 -- moderate to strong
747.7 -- moderate
726.9 -- 2nd largest absorption
693.4 -- largest absorption
681.9 -- medium
663.1 -- tied for 3rd largest absoprtion

[jjblt]

I have narrowed it down to:

1. 4-Chlorobenzophenone, lit. mp 78
2. Diphenyl phthalate, lit. mp 74

The reason why I doubt 4-Chlorobenzophenone is because of my negative results for halogens. 
The reason why I doubt it's diphenyl phthalate is because that carbonyl stretch is above 1700.  Isn't my stretch at 1648 too low?


If it's too hard to help without seeing my H NMR and IR, I can figure out a way to post pics.  Thanks in advance everyone. 

[jjblt]

Okay, this should *delete me* Here's the IR: