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Proton NMR A level Chemistry help!!!

SongBird2020

Hey guys i need help with proton NMR. Basically when you are identifying the type of proton from the proton NMR, how do you apply that to the information given and what does the highlighted alkyl group on most marking schemes refer to? Sorry if this sounds confusing but its so hard to explain. I just really struggle to get the actual structure in the end. I would appreciate any help/advice on this since the exam is tomorrow, thanks !!!!

Reply 1

charco

Study Forum Helper

Original post by Loreto2018

1. look at the splitting pattern
singlet = has no hydrogens on the neighbouring carbon
doublet = has one hydrogen on the neighbouring carbon
triplet = has two hydrogens on the neighbouring carbon
quartet = has three hydrogens on the neighbouring carbon

can you spot a pattern here?

2. Look at the integral (either numerical or an integrals sign)
relative height 1 = 1 hydrogen atom signal
relative height 2 = 2 hydrogen atom signal
relative height 3 = 3 hydrogen atom signal

can you spot a pattern here?

3. Look at the chemical shift and try to match it from the table of chemical shifts.

For example delta = 0.9, typical shift for hydrocarbon hydrogens

Remember that the chemical shifts get larger when attached to electronegative atoms.
Chemical shifts are not exact, but occur over a range depending on environment and solvent.