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- https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Nuclear_Magnetic_Resonance%3A_Applications_to_Organic_Chemistry_(Roberts)/zz%3A_Back_Matter/10%3A_Index
- https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Nuclear_Magnetic_Resonance%3A_Applications_to_Organic_Chemistry_(Roberts)/02%3A_The_Chemical_Shift
- https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Nuclear_Magnetic_Resonance%3A_Applications_to_Organic_Chemistry_(Roberts)/03%3A_Spin-Spin_Splitting/3.08%3A_Spin-Spin_Couplings_in_Rigid_SystemsFirst, as shown for styrene oxide, the protons of adjacent methylenes in a rigid system will generally have at least two spin-spin coupling constants which correspond to interactions between the vario...First, as shown for styrene oxide, the protons of adjacent methylenes in a rigid system will generally have at least two spin-spin coupling constants which correspond to interactions between the various combinations of cis and trans protons. Second, J for protons on adjacent carbons shows a strong angular dependence and, as a result, the couplings in more or less rigid systems vary between zero and the values normally encountered for open-chain substances.
- https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Nuclear_Magnetic_Resonance%3A_Applications_to_Organic_Chemistry_(Roberts)/05%3A_Nuclear_Quadrupole_Relaxation_Effects_and_Double_Resonance/5.03%3A_Proton_N-H_Resonance_of_Pyrrole._Double_ResonanceApparently, the 14N nucleus in pyrrole is undergoing relaxation at just the right rate to cause the protons attached to it to give the broadest possible line intermediate between the singlet and tripl...Apparently, the 14N nucleus in pyrrole is undergoing relaxation at just the right rate to cause the protons attached to it to give the broadest possible line intermediate between the singlet and triplet patterns. 5-3, this may be achieved by raising or lowering the temperature so as to change the rates of tumbling of the molecules and thus influence the effectiveness of the quadrupole relaxation of the nitrogen nucleus.
- https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Nuclear_Magnetic_Resonance%3A_Applications_to_Organic_Chemistry_(Roberts)/04%3A_Nuclear_Magnetic_Resonance_and_Reaction_Kinetics/4.02%3A_Relationship_between_Resonance_Line_Shapes_and_Exchange_RatesIn general, there will be a gradual change in the appearance of a resonance due to a magnetic nucleus in a particular chemical environment as the mean lifetime in that environment decreases. Gutowsky ...In general, there will be a gradual change in the appearance of a resonance due to a magnetic nucleus in a particular chemical environment as the mean lifetime in that environment decreases. Gutowsky 2 has shown that the point at which the separate lines just coalesce corresponds to \(\tau\)A equal to \(\sqrt 2 (\pi\delta\) AB H) -1 sec when (\(\delta\) AB H) is expressed in cycles per second or 2\(\sqrt 2 (\pi\delta\) AB H) -1 when (\(\delta\) AB H) is expressed in radians per second.
- https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Nuclear_Magnetic_Resonance%3A_Applications_to_Organic_Chemistry_(Roberts)/zz%3A_Back_Matter/22%3A_Appendix_B
- https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Nuclear_Magnetic_Resonance%3A_Applications_to_Organic_Chemistry_(Roberts)/01%3A_Introduction_-_The_Nuclear_Resonance_Phenomenon/1.11%3A_Properties_of_Magnetic_Nuclei_of_Interest_to_Organic_ProblemsA more mathematical treatment of nuclear resonance absorption is presented in Appendix A for the purpose of elucidating the differences between the absorption and dispersion modes and the nature of ce...A more mathematical treatment of nuclear resonance absorption is presented in Appendix A for the purpose of elucidating the differences between the absorption and dispersion modes and the nature of certain probe adjustments which may influence the shapes of resonance signal curves.
- https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Nuclear_Magnetic_Resonance%3A_Applications_to_Organic_Chemistry_(Roberts)/02%3A_The_Chemical_Shift/2.08%3A_Chemical_Shifts_and_Organic_Structure_Determinations._General_ConsiderationsAn example taken from steroid chemistry is the tetracyclic ketol obtained by Johnson and coworkers 18 by way of an aldol condensation and assigned the structure shown below by virtue of its conversion...An example taken from steroid chemistry is the tetracyclic ketol obtained by Johnson and coworkers 18 by way of an aldol condensation and assigned the structure shown below by virtue of its conversion through the action of strong base and then by a long sequence of synthetic steps to naturally occurring steroidal hormones.
- https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Nuclear_Magnetic_Resonance%3A_Applications_to_Organic_Chemistry_(Roberts)/04%3A_Nuclear_Magnetic_Resonance_and_Reaction_Kinetics/4.08%3A_Proton_Exchange_in_Ammonia_and_Ammonium_IonsThe line at the lowest field represents the proton resonance absorption of those ammonia molecules having nitrogen with a magnetic quantum number +1, while the center and high-field lines correspond t...The line at the lowest field represents the proton resonance absorption of those ammonia molecules having nitrogen with a magnetic quantum number +1, while the center and high-field lines correspond to the nitrogen nuclei with magnetic quantum numbers 0 and -1, respectively.
- https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Nuclear_Magnetic_Resonance%3A_Applications_to_Organic_Chemistry_(Roberts)/02%3A_The_Chemical_Shift/2.01%3A_Introduction._The_Chemical-shift_ParameterField-dependent differences between resonance line positions are called "chemical shifts" and arise because the lines of force of the applied magnetic field tend to be turned away from the nuclei by a...Field-dependent differences between resonance line positions are called "chemical shifts" and arise because the lines of force of the applied magnetic field tend to be turned away from the nuclei by a diamagnetic shielding effect (but can also be turned in by a second-order paramagnetic effect) of the surrounding electrons.
- https://chem.libretexts.org/Bookshelves/Organic_Chemistry/Nuclear_Magnetic_Resonance%3A_Applications_to_Organic_Chemistry_(Roberts)/04%3A_Nuclear_Magnetic_Resonance_and_Reaction_Kinetics/4.04%3A_Ethyl_Acetoacetate_and_Its_Enol_FormThe detection of the separate resonances of the keto and enol forms shows that the enol and keto forms are not interconverted rapidly at room temperature, and this is in agreement with the observation...The detection of the separate resonances of the keto and enol forms shows that the enol and keto forms are not interconverted rapidly at room temperature, and this is in agreement with the observation that the enol and keto forms can be separated by "aseptic distillation" and separately preserved at low temperatures.
