Hello! I have a few questions related to NMR that I would love clarification on, thank you so much!

17 -Downfield menas more deshielded or less electron cloud on the proton or it is close to some more electronegative atom.
Here H on sp2 carbon is most deshielded as in aromatic ring.Check the chemical shiift values-
D is a vinylic proton (attached to a C=C), which typically appears around 5–6.5 ppm.

The others are more upfield:

A = ester OCH₃ (~3.7 ppm)

B = CH₂ alpha to carbonyl (~2.1–2.5 ppm)

C = allylic/alkyl proton (~1.5–2.5 ppm range depending exact position)

Quote from: amimi on February 17, 2026, 12:47:33 AMHello! I have a few questions related to NMR that I would love clarification on, thank you so much!

Most deshielded will have highest chemical shift value and will appear more downfield.Least deshielded which is E (sp3C-H) are more uplfieldwith lowest chemical shift value.
So the order is
E<D<A<C<B
E = simple alkyl CH₃ (most upfield, ~0.9 ppm)

D = CH₂ next to C=O (deshielded, ~2.1–2.5 ppm)

A = OCH₃ (attached to O, ~3.2–3.8 ppm)

C = vinylic proton in conjugated system (enone), ~6–7 ppm

B = aromatic protons (usually ~7–8 ppm, furthest downfield here)