Module 3 - Benjamin-Mills

USING NUCLEAR MAGNETIC RESONANCE (n.m.r.) SPECTROSCOPY FOR STRUCTURE DETERMINATION
EP2.3
c
Figures 8, 9 and 10 show the n.m.r. spectra of aminoethane,
1-aminopropane and propanamide respectively.
i Draw the full structural formula of each of these molecules.
ii Identify the hydrogen atoms responsible for each of the signals in the
n.m.r. spectra and, where possible, comment on the shape of these
signals.
3H
Figure 8 The n.m.r. spectrum of aminoethane
Absorption
2H
2H
TMS
10
9
8
7
6
5
4
3
2
1
0
Chemical shift
3H
Figure 9 The n.m.r. spectrum of 1-aminopropane
Absorption
2H
2H
2H
TMS
10
9
8
7
6
5
4
3
2
1
0
Chemical shift
3H
Figure 10 The n.m.r. spectrum of propanamide
Absorption
2H
TMS
2H
10
9
8
7
6
5
4
3
2
1
0
Chemical shift
„ Salters Advanced Chemistry 2000 – see Copyright restrictions
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