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Topic: Reporting NMR data  (Read 3531 times)

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Offline oister

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Reporting NMR data
« on: November 06, 2015, 07:46:00 AM »
I'm having some trouble reporting my H NMR data correctly.
I have a benzene ring substituted at position 1, 3 and 4. This leaves me with 3 aromatic peaks; One of them is a singlet (8.2), but with meta coupling, so it looks like a doublet. In my practical report, should I just say it's a singlet (as no ortho coupling) or should I say it's a doublet (due to meta coupling)?
Thanks :)

Edit... Also, another peak is a double doublet (7.95), first due to the ortho coupling, and then meta. Same question here; should I report this as a d or dd?


Offline Corribus

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Re: Reporting NMR data
« Reply #1 on: November 06, 2015, 09:40:30 AM »
If it's a doublet, report it as a doublet (d, with coupling value in Hz). If it's a doublet of doublets, report it as a doublet of doublets (dd, with coupling values in Hz).
What men are poets who can speak of Jupiter if he were like a man, but if he is an immense spinning sphere of methane and ammonia must be silent?  - Richard P. Feynman

Offline Irlanur

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Re: Reporting NMR data
« Reply #2 on: November 07, 2015, 10:33:06 AM »
The multiplicity you report is the multiplicity you see. Otherwise you will quikly run into problems, because in priniple there is a coupling constant between all the nuclei. What you see only depends on the resolution.

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