Organic Chemistry: Unknown

[peter567]

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I know this probably isn't the appropriate forum, but I'm desperate.

My professor gave us a liquid unknown, and I have to identify it. I have the NMR and IR spectra, and boiling point. If there's someone that knows this stuff, please help me!!

Here are the spectra:

http://www.flickr.com/photos/94641931@N04/8616080537/
http://www.flickr.com/photos/94641931@N04/8616089763/in/photostream

Any help at all would be GREATLY appreciated!

 

[kss1025]

I know this probably isn't the appropriate forum, but I'm desperate.

My professor gave us a liquid unknown, and I have to identify it. I have the NMR and IR spectra, and boiling point. If there's someone that knows this stuff, please help me!!

Here are the spectra:

http://www.flickr.com/photos/94641931@N04/8616080537/
http://www.flickr.com/photos/94641931@N04/8616089763/in/photostream

Any help at all would be GREATLY appreciated!

Just from looking at it, I would expect a C=O and a C-N to be somewhere in there. Also, the structure is aliphatic.... I hope that helps somewhat. It's hard to determine without any more hints, but then again, I'm not the best with spectra.

 

[Skrumpy]

I know this probably isn't the appropriate forum, but I'm desperate.

My professor gave us a liquid unknown, and I have to identify it. I have the NMR and IR spectra, and boiling point. If there's someone that knows this stuff, please help me!!

Here are the spectra:

http://www.flickr.com/photos/94641931@N04/8616080537/
http://www.flickr.com/photos/94641931@N04/8616089763/in/photostream

Any help at all would be GREATLY appreciated!

IR Spectroscopy Correlation Table
Proton NMR Table

 

[DrDrugs2012]

You can make educated guesses, but without a complete proton spectrum, you have a hard time assigning protons. The cutoff at the top on the spectrum means you have no idea how many protons are associated with each signal.

Also, was proton spectrum done in deuterium or DMSO? that makes a difference because values of some proton species shift based on the solvent.

Previous poster is probably correct -
IR @ 1700-1800 is probably a C=O functional group (lack of an OH stretch or a peak at 2700-2800 means probably not carboxylic acid or aldehyde and more likely ketone)
IR @ 2300-2400 is probably a nitrile group
IR <3000 shows probable aliphatic moiety and absence of >3000 shows lack of aromaticity (or do I have that backwards... I forget... its been about 10 or 15 years since I have seen one of these...)

There may be a C=C bond, so that quartet may actually be a double doublet. When piecing it together, keep an eye out on that. This is why you need measurements of the proton count (based on the rise of the graph line).

 

[peter567]

You can make educated guesses, but without a complete proton spectrum, you have a hard time assigning protons. The cutoff at the top on the spectrum means you have no idea how many protons are associated with each signal.

Also, was proton spectrum done in deuterium or DMSO? that makes a difference because values of some proton species shift based on the solvent.

Previous poster is probably correct -
IR @ 1700-1800 is probably a C=O functional group (lack of an OH stretch or a peak at 2700-2800 means probably not carboxylic acid or aldehyde and more likely ketone)
IR @ 2300-2400 is probably a nitrile group
IR <3000 shows probable aliphatic moiety and absence of >3000 shows lack of aromaticity (or do I have that backwards... I forget... its been about 10 or 15 years since I have seen one of these...)

There may be a C=C bond, so that quartet may actually be a double doublet. When piecing it together, keep an eye out on that. This is why you need measurements of the proton count (based on the rise of the graph line).

Yes the first peak is TMS. Everything should be shifted. Sorry forgot to mention that

 

[Reduc]

Yes the first peak is TMS. Everything should be shifted. Sorry forgot to mention that

That was pretty evil of you but I guess I should of remembered to always look for TMS. Tried to solve it yesterday on my "study break" are you we're not missing any additional information your teacher could of given you?

 

[peter567]

That was pretty evil of you but I guess I should of remembered to always look for TMS. Tried to solve it yesterday on my "study break" are you we're not missing any additional information your teacher could of given you?

haha sorry! all i have is the nmr, ir, BP, and pH