Concept explainers
Interpretation:
Electron delocalization in cyclooctatetraene based on the location of signal in
Concept introduction:
Nuclear Magnetic Resonance (NMR) is one of the most capable analytical techniques used for determining the
Few elements, such as
In
Induced magnetic field consists of electricity generated from movement in a magnetic field.
The position of a signal on x-axis in the
The number of signals in
The area covered by the signal is proportional to the number of equivalent protons causing the signal.
The hydrogen atoms on adjacent carbon atoms split the signal into two or more peaks. One, two or three hydrogen atoms split the signal into two, three or four peaks described as doublet, triplet or quartet respectively.
A decrease in the electron density around a proton deshields the signal downfield at a larger value of chemical shift.
An increase in electron density shields the signal upfield at a lower value of chemical shift.
The number of signals in NMR spectra shows the number of different chemical environments in a molecule.
Aromatic protons give signal downfield between
Alkene protons give signal upfield between
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Organic Chemistry
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- Organic ChemistryChemistryISBN:9781305580350Author:William H. Brown, Brent L. Iverson, Eric Anslyn, Christopher S. FootePublisher:Cengage Learning