HW 3 Multinuclear NMR Name:
Points: C6800 Date:
Max. 100 points Spring 2014 Version A
1. Decide which isomer of the compounds below is present when the experimental value of
olefinic proton shift in the 1
H NMR spectrum is 8.22 ppm. Use tables of increments.
2. How would you distinguish these two isomers. Give the symmetry point groups of the
molecules. Calculate chemical shifts of aromatic protons and carbons.
OH
OH
3. Draw possible stereoisomers of the following molecule, assign their symmetry space
groups and decide how many signals of CH groups will be present in the 1
H NMR spectra:
R
R
PhPh
4. Mark protons as C2, homotopic (H), enantiotopic (E) and diastereotopic (D) in the
following molecules:
5. Calculate relative populations of 207
Pb isotopomers in the molecule of plumbane:
H3C
Pb
H3C
H3C
C C Pb
CH3
CH3
CH3
R R
Ph Ph
OO
H
H
H
H
H
Me
H
Me
Me
H
H
Me