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More peaks in NMR spectra than expected!!

I have an NMR spectra which is showing finer splitting than expected (is not obeying the n+1 rule) for H1 NMR. Can somebody explain to me how this could have occured only i think i may have miscalculated something?
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Original post by bluenicey

Original post by bluenicey
I have an NMR spectra which is showing finer splitting than expected (is not obeying the n+1 rule) for H1 NMR. Can somebody explain to me how this could have occured only i think i may have miscalculated something?


Any chance of a picture of the spectrum and the name of the product?
Solvent peaks
impurities (what purifications did you perform?) or solvent peaks. What solvent have you used? Have you checked the chemical shifts that it produces?

Either that or it's not your product. Either way the N+1 rule is solid, and there is no sizeable coupling beyond 3 bonds separation (even if there is, the constant will be so small to cause the peaks to overlap and look like a singlet).

A pic of the spectra would help vastly.
You might be seeing long range coupling if the machine it's run on is good enough, or you may see some examples of restricted rotation or locked conformation effects.

Assuming it's the product you expect in the first place :p:
the protein might have different subconformations which can interchange concomitantly

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