Trouble Identifying this Organic Unknown

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The discussion centers on identifying a compound based on physical data and an IR spectrum that do not match known compounds. The sample is described as a clear, yellowish liquid with a fruity smell, a boiling point of approximately 165.5°C, and a refractive index of 1.55 at 20°C. The IR spectrum shows key features indicative of a carboxylic acid, including an OH shoulder, a C=O band at 1703 cm-1, and C-O bond signals. Participants suggest that the fruity smell points towards an ester, but caution against relying solely on odor for identification. They recommend using the IR data to eliminate many compounds from the provided list, emphasizing the importance of confirming whether the sample is a single compound or potentially contaminated. Suggestions include measuring the melting point to assess purity and further narrowing down the list based on boiling point data. Overall, the conversation highlights the need for careful analysis and consideration of potential contaminants in compound identification.
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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!
 
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Smell suggests ester, are you sure about BP?

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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.
 
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)
 
PhaseShifter said:
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.
 
Handbook of Chemistry and Physics. You should be able to eliminate a ton of those from BP alone.
 

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