[Mark_Z]

I have a sample of what was claimed to be 1,4-cyclohexanediol as a mixture of cic/trans isomers. There are 5 C13 peaks in the NMR that I did on this compound. The vendor claims that there should be 4 peaks representing the 2 isomers, and the 5th peak is maybe due to acetone. I disagree with the vendor. All the NMR predictive softwares I have used says there should only be 2 peaks.

Any thoughts?

[Dan]

Your NMR software probably doesn't predict differences arising from the stereoisomerism.

Each isomer should give 2 peaks.

What are the shifts and the NMR solvent used?

[Mark_Z]

My friend did the NMR for me and didn't tic mark the actual chemical shifts. Near as I can make out the shifts are 31, 33, 37, 66, and 68 ppm. Solvent is DMS-d6

[Mark_Z]

Stupid wireless keyboard. Make that solvent DMSO-d6

[Mark_Z]

I hate admitting I'm wrong, but I was wrong. Went to http://sdbs.db.aist.go.jp/sdbs/cgi-bin/direct_frame_top.cgi, and looked up the 2 isomers. There should be 4 peaks for a mixture of the isomers, separated by about 2 ppm.