Help with NMR multiplicity

  • Thread starter etotheipi
  • Start date
  • #1
I was doing a question that wanted you to determine the structure given a molecular formula and an NMR spectrum. The following was the answer:
1583685998403.png

I'm unsure as to how the multiplicities were obtained. For ##X##, the neighbouring carbon ##Y## has 2 hydrogens, so this peak is a triplet (OK so far!).

But for ##Y##, the neighbouring carbon (##X##?) has 3 hydrogens so shouldn't that peak should be a quartet? And ##Z##'s neighbouring carbon has no hydrogens so this peak should just be a singlet. This also agrees with the integration, since both ##X## and ##Z## have 3 hydrogens but ##Y## only has 2. I am not sure why they have put it the other way around?

Thank you!
 

Answers and Replies

  • #2
DrStupid
2,167
501
I agree with you argumentation. It looks like the assignment is wrong.
 
  • #3
I agree with you argumentation. It looks like the assignment is wrong.

Ah, awesome. Vindication!
 
  • #4
chemisttree
Science Advisor
Homework Helper
Gold Member
3,712
704
It’s wrong online in some places as well. This is the wrong assignment!
https://physics.bgu.ac.il/COURSES/LAB_C/NMR/htbooks/nmr/spectra/mek-016.gif
 

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