Learner Resource 2 – Analysing a proton NMR
spectrum
Use the list of ‘golden rules’ below to help you analyse the proton NMR spectrum provided.
Golden rules for analysing proton NMR spectra:
1. Look at the peaks in the spectrum. How many different proton environments are there?
2. Label each peak with a letter.
3. Write down the chemical shift value for each peak.
4. Use the Data Sheet to find possible structures for each peak.
5. Look at the splitting for each peak. Is it a singlet (no adjacent protons), doublet (one
adjacent proton), triplet (two adjacent protons), quartet (three adjacent protons) or multiplet
(complex combination of adjacent protons). Note that ‘adjacent’ means the protons are on
the carbon ‘next door’.
6. Look at the integration value for each peak, if provided; this may be a ratio or a whole
number. The relative integration values give you information about the number of protons in
each environment. A whole number above 3 often means there are multiple equivalent
environments.
The proton NMR spectrum of 1,3-dioxane is shown below.
1,3-dioxane
Identify the protons responsible for each peak and explain the splitting patterns.
Peak label
Chemical shift value /
ppm
Possible
structure
Number of
peaks
Splitting; how many
adjacent protons?
A
B
C
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Identification of Unknowns
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© OCR 2015