15: Nuclear Magnetic Resonance Spectroscopy
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- explain how 1H NMR spectrometers work - refer to section 12.1
- interpret chemical shifts of 1H NMR spectra as they relate to shielding and deshielding - refer to section 12.2 and 12.14
- explain the delta scale of 1H NMR spectra - refer to section 12.3
- recognize equivalent protons within an organic compound - refer to section 12.4
- correlate functional group structural features with chemical shifts - refer to section 12.5
- determine the proton ratio from 1H NMR spectra peak integration data - refer to section 12.6
- explain and interpret spin-spin splitting patterns in 1H NMR spectra - refer to section 12.7
- explain and interpret spin-spin splitting patterns in 1H NMR spectra - refer to section 12.8
- describes examples of some uses of 1H NMR spectroscopy - refer to section 12.9
- explain how 13C NMR spectrometers work - refer to section 12.10
- interpret the chemical shifts of 13C NMR spectra to determine the structural features of organic compounds - refer to section 12.11 and 12.14
- explain how DEPT (distortionless enhancement by polarization transfer) is used to determine the number of hydrogens bonded to each carbon - refer to section 12.12
- describes some uses of 13C NMR spectroscopy - refer to section 12.13
- 15.1: Theory of Nuclear Magnetic Resonance (NMR)
- Nuclear Magnetic Resonance (NMR) Spectroscopy uses the electromagnetic radiation of radio waves to probe the local electronic interactions of a nucleus.
- 15.2: NMR Spectra - an introduction and overview
- The NMR spectrum for methyl acetate is used as an example to introduce NMR spectra.
- 15.3: Chemical Shifts and Shielding
- The chemical shift is the resonant frequency of a nucleus relative to a standard in a magnetic field (often TMS). The position and number of chemical shifts provide structural information about a molecule. Some factors that influence chemical shifts are discussed.
- 15.4: ¹H NMR Spectroscopy and Proton Equivalence
- In an applied, external magnetic field, protons in different locations of a molecule have different resonance frequencies, because they are in non-identical electronic environments. Equivalent protons experience the same electronic environment.
- 15.5: Functional Groups and Chemical Shifts in ¹H NMR Spectroscopy
- An approximate idea of the chemical shifts of the most common types of protons is helpful when interpreting 1H NMR spectra.
- 15.6: Integration of ¹H NMR Absorptions- Proton Counting
- The ratio of proton signal areas correlates with the proton ratio of a compound providing useful structural information.
- 15.7: Spin-Spin Splitting in ¹H NMR Spectra
- The peaks can be split into multiplets when the magnetic field experienced by the protons of one group is influenced by the spin arrangements of the protons in an adjacent group. Splitting occurs primarily between non-equivalent hydrogens that are separated by three bonds.
- 15.8: More Complex Spin-Spin Splitting Patterns
- Some factors that create more complex 1H NMR spectra are introduced.
- 15.9: Uses of ¹H NMR Spectroscopy
- The efficacy of two synthetic organic reactions are compared and discussed using data from 1H NMR spectra.
- 15.10: Sample NMR Spectra
- Several animated proton NMR spectra are explored.