Qualitative Organic Analysis – CH 351 NMR Spectroscopy Bela Torok Department of Chemistry University of Massachusetts Boston Boston, MA
Qualitative Organic Analysis –CH 351
NMR Spectroscopy
Bela TorokDepartment of Chemistry
University of Massachusetts BostonBoston, MA
General Aspects
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Theoretical base of NMR spectroscopy
General Aspects
3
General Aspects
Theoretical base of NMR spectroscopy
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General Aspects
Theoretical base of NMR spectroscopy
General Aspects
Schematic diagram of an NMR spectrometer
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General Aspects
Handling
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General Aspects
Magnetic field
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General Aspects
Pulsed NMR
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General Aspects
Relaxation
Spin-Lattice Relaxation (longitudinal or T1)
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General Aspects
Relaxation
Spin-Spin Relaxation (T2)
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General Aspects
Shielding
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General Aspects
NMR active nucleii (elements)
Odd number of protons and/or neutrons
(strongly depends on natural abundance)1H , 2H (3H)13C15N18O check!19F31P
and many others
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General Aspects – 1H NMR Spectroscopy
Equivalent vs. Nonequivalent nucleii
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General Aspects – 1H NMR Spectroscopy
Equivalent vs. Nonequivalent nucleii
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General Aspects – 1H NMR Spectroscopy
Equivalent vs. Nonequivalent nucleii
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General Aspects – 1H NMR Spectroscopy
Equivalent vs. Nonequivalent nucleii
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General Aspects – 1H NMR Spectroscopy
Equivalent vs. Nonequivalent nucleii
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General Aspects – 1H NMR Spectroscopy
Equivalent vs. Nonequivalent nucleii
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Chemical Shift
General Aspects – 1H NMR Spectroscopy
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General Aspects – 1H NMR Spectroscopy
Chemical Shiftδ = dist. down field from TMS (Hz) / op. frequency (MHz)
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General Aspects – 1H NMR Spectroscopy
Chemical Shift
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General Aspects – 1H NMR Spectroscopy
Chemical Shift
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General Aspects – 1H NMR Spectroscopy
Chemical Shift
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General Aspects – 1H NMR Spectroscopy
Chemical Shift
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General Aspects – Mass Analyzers General Aspects – 1H NMR Spectroscopy
Chemical Shift
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General Aspects – 1H NMR Spectroscopy
Chemical Shift
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General Aspects – 1H NMR SpectroscopyChemical Shift
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General Aspects – 1H NMR Spectroscopy
Chemical Shift
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General Aspects – 1H NMR Spectroscopy
Chemical Shift
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General Aspects – 1H NMR Spectroscopy
Chemical Shift
Diamagnetic anisotropy
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General Aspects – 1H NMR Spectroscopy
Chemical Shift
Diamagnetic anisotropy
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General Aspects – 1H NMR Spectroscopy
Chemical Shift Diamagnetic anisotropy
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General Aspects – 1H NMR Spectroscopy
Chemical Shift Diamagnetic anisotropy
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General Aspects – 1H NMR Spectroscopy
Chemical Shift Diamagnetic anisotropy
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General Aspects – 1H NMR Spectroscopy
Integration
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General Aspects – 1H NMR Spectroscopy
Integration
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General Aspects – 1H NMR Spectroscopy
Integration
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General Aspects – 1H NMR Spectroscopy
Integration
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General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling splitting of the signals
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General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling splitting of the signals
N+1 rule
(2I+1 in general)
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General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling splitting of the signals
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General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling
General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling
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General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling
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General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling
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General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling
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General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling long range splitting
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General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling
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General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling
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General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling
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General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling
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General Aspects – 1H NMR Spectroscopy
Geminal Coupling Spin-Spin Coupling
General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling
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General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling
General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling
General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling
General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling
General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling – Coupling Constant
General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling – Coupling Constant
General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling – Coupling Constant
General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling – Coupling Constant
General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling – Splitting Diagram
General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling – Splitting Diagram
General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling – Splitting Diagram
General Aspects – 1H NMR Spectroscopy
Spin-Spin Coupling – Splitting Diagram
General Aspects – 1H NMR Spectroscopy
Enantiotopic hydrogens
General Aspects – 1H NMR Spectroscopy
Diastereotopic hydrogens
General Aspects – 1H NMR Spectroscopy
Diastereotopic hydrogens
General Aspects – 1H NMR Spectroscopy
Time dependence - slow method
General Aspects – 1H NMR Spectroscopy
Time dependence - slow method
General Aspects – 1H NMR Spectroscopy
Time dependence - slow method
Effect of the medium
General Aspects – 1H NMR Spectroscopy
General Aspects – 1H NMR Spectroscopy
Resolution of spectra