GBALA

I am trying hard to decode a structure of my compound. After a lot of efforts, reading and going through various spectras I got some picture of this compound that it could be a hydroxy fatty acid or ester. It would be grateful if someone tells me how the peak value at 2.29 ppm in the H-NMR spectrum either can be assigned to that of CH2COOH or CH2COO. The integration values are not conclusive. The peak is triplet. Thank you in advance.

I like to check one of my fraction which was eluted with 100% hexane from column and the content is high and showing single spot on normal phase TLC. The spot lies on the solvent front as the mobile phase solvent chosen is 100% hexane. So it could be mixture of hydrocarbons. I would like to know how many compounds this mixture does contain. If reverse phase TLC would be an option what is the best mobile phase solvent system to achieve good resolution? Help would be much appreciated.

i would disagree with ur thoghts. i found a way to dissolve the precipitate by dissolving it in more volume of water. it dissolved. still running out of idea what could it be. thinking that it could be water soluble tannins or their esters.

I know very little about bark and I did extraction of bark of a tree with water by cold extraction. It yielded good quantity of crude extract and when I applied the same onto Diaion hp-20 column i got fractions. The first fraction which is eluted with water is in reddish cherry color and no observable TLC spot. When I kept this particular fraction overnight at RT some white color compound started precipitating. It looked great for a moment but the problem is when I again tried to dissolve it in water it didnt dissolve. What could be wrong here? What kind of compound it could be? Many more thanks in advance.

What if it is 68 or 70 protons? Please explain me a bit. Also how a solvent that is used for extraction and isolation influence NMR spectrum? Please share your thoughts. It would be more helpful. With my little experience it is not water contamination. Also I have taken NMR spectrum of this compound for three times and all three times I ended up with the same intense peak with slightly varying integral values. sorry that i couldnt attach the spectrum. It is yet to be identified what it is.

Chloroform

Recently took a NMR spectrum, of my natural product sample and it showed intense -CH2 peak at 1.2 ppm in the H NMR spectrum. But the integration value mentioned is 69. Is it an error? If so how can i overcome this? Appreciate your suggestions. Note that C13 showed only 13 peaks

Yes sir i am about to carry out some mass spectra. The boiling point of this compound is 62 degree. Can it be worth if i go for GC-MS?

good guess sir. But there is no possibility of COOH group. If it is highly symmetrical how can i decode the spectrum to find out the structure?

I isolated a compound from plant source and it is only soluble in hot chloroform with the melting point of 60 degree. I have taken H-NMR and it clearly shows the characteristic peak of -CH2 group @ 1.2 ppm with the integration value of 69 which suggests that it could be fattyacid or hydrocarbon. But C-13 NMR gave relatively less number of peaks that is only 8 peaks in the spectrum. How can I correlate with 8 carbons and more than 70 protons. Please help me through.

Sorry for not able to provide my spectrum. I accepted your point that IR analysis alone wont enough for finding the structure of an unknown compound. I got HNMR spectrum also but there is no peak related to carboxylic acid. The final peak at HNMR spectrum is at 4 ppm and it is a triplet. No peak beyond that ppm. If it is due to a hydroxy containing compound's contamination then is it likely to end up with a small broad peak at ~3300?

None of the method you mentioned. I have given my sample in a near by institute and they analyzed by simply taking nearly 1 mg onto a panel and started taking the spectrum. This is my first time IR experience and help me what went wrong with my spectrum. Thanks for your time and consideration

I got a IR spectrum of my unknown compound and it shows a peak which is sharp(small in size) but not as strong as it should be for a carbonyl stretching at 1732. Also a small and bit broad peak at 3356 which confuses me the possibility of O-H stretching which is normally very broad. Please help me regarding this