qualitative organic analysis – ch 351 nmr...

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

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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