Exercise plus Solution – Quick PDF overview
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1
H NMR spectrum
recorded at 250.13 MHz
C
3
H
7
NO
2
measured in CDCl
3
Deduce the structure!
Solution
C
3
H
7
NO
2
Basic considerations
Double bond equivalents,
number of signal groups,
chemical shifts
We don’t know about the oxidation number of nitrogen. Therefore, one
cannot determine the number of double bond equivalents beyond doubt.
We observe three signal groups at approx. 4.4 ppm, 2.1 ppm and 1.0
ppm. A more precise indication of the chemical shift is not necessary
here.
C
3
H
7
NO
2
Basic considerations
Integration
measured integrals [a.u.] - 1.00 1.00 1.52
sum of all integrals [a.u.] - 3.52
proportionality coeffcient - 1.99 H/a.u.
a.u. – arbitrary unit
H – number of protons in each signal group
2H 3H2H
Number of protons in each signal group