The reading of Exp’t 4 (salicylic acid) lab reports informed me that many 201 students struggled with the complexities of the proton NMR spectrum. The NMR of salicylic acid is complicated, no doubt about it, but it can be understood and it provides a great introduction to the types of coupling patterns seen in organic compounds.
Here are two readings that I strongly recommend:
- Combination Coupling Patterns in Salicylic Acid’s 1H NMR Spectrum (by me)
- Sorrell, “13.4 Spin Couplings in More Complex Systems” (p. 420)
Sorrell’s treatment is excellent, but it might help to read my essay first because it explains a spectrum about which you have already thought a great deal.