Do you need some more hints on these questions? Check here!
- If the magnetic fields of two protons can interact
via s- and p- electrons in bonds connecting
the two protons directly, or indirectly over additional nuclei, then
their energy levels in the external magnetic field of the spectrometer
will show additional splittings. Because of that additional transitions
with only small differences in energy become possible.
- Since these interactions are mediated by bond
electrons, this phenomenon is referred to as through-bond
- In the most basic case, when only n equivalent
protons X are coupling to the proton A, the following relationship
exists between the number of coupling protons and the multiplicity MA
of the signal dA
- In this case the relative intensities of the lines in
various multiplets follow characteristic patterns:
||1 : 1
||1 : 2 : 1
||1 : 3 : 3 : 1
||1 : 4 : 6 : 4 : 1
Otherwise try to apply your knowledge in the next excercise.
| Draw a schematic NMR spectrum of the molecule R2CH-CH3!
Compare your solution to the correct answer on page