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stuartischees
Oct21-09, 06:41 PM
Alright, I've got a bunch of physical data and an IR Spectrum, but somehow it doesn't seem to match up with any compound I find through google. Even worse, I have a list of compounds it should be and there's still no obvious winner. Any help is dearly appreciated.

Clear, yellowish liquid. Fruity smell.

BP ~ 165.5C
Refractive index ~ 1.55 @ 20C

IR Specrtum:
Obvious OH shoulder, looks like a carboxylic acid
C=O band at 1703
Presumed C-O bond at 1204
Small band at 3064
Moderate bands at 2820 and 2850

Possible Unknowns:
Cyclohexanone
Bromobenzene
1-Bromobutane
2-Chloroethanol
Phenylacetylene
1-Octanol
Ethyl Benzoate
Propionic Acid
Benzaldehyde
1-Octene

Again, all help is appreciated!
Borek
Oct22-09, 04:35 AM
Smell suggests ester, are you sure about BP?

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pzona
Oct22-09, 05:05 PM
Well based on your IR readings you should be able to eliminate at least half the compounds on your list. I wouldn't go just on smell, but like Borek said, a sweet/fruity smell suggests an ester.
PhaseShifter
Oct22-09, 10:11 PM
Are you sure this is a single compound, and isn't contaminated by anything else that would appear in the IR spectrum? (i.e. ester contaminated with alcohol or acid left over from synthesis)
pzona
Oct23-09, 11:32 AM
Are you sure this is a single compound, and isn't contaminated by anything else that would appear in the IR spectrum? (i.e. ester contaminated with alcohol or acid left over from synthesis)

This is a good point; I hadn't thought of this. Depending on the equipment you have available, you might want to cool it down enough to get a melting point, which can give you a general idea of the purity.
gravenewworld
Oct23-09, 06:41 PM
Handbook of Chemistry and Physics. You should be able to eliminate a ton of those from BP alone.