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530 CHAPTER 15 
 
(c) To determine the expected splitting pattern for the signal corresponding to Hc, we must consider the effects of the 
two non-equivalent neighbors, Ha and Hb, The former is coupled to Hc with a coupling constant Jac (17 Hz), and the 
latter is coupled to Hc with a coupling constant Jbc (1 Hz). We begin with the larger coupling constant (Jac in this case), 
which splits the signal into a doublet. Then, each peak of this doublet is then further split into a doublet because of the 
effect of Hb. The result is a doublet of doublets. 
 
 
15.19. 
(a) This compound is expected to produce four signals in 
its 1H NMR spectrum. For each signal, its expected 
chemical shift, multiplicity, and integration are shown. 
 
 
 
(b) This compound has rotational and reflectional 
symmetry: 
 
 
So we expect its 1H NMR spectrum to exhibit only five 
signals, corresponding with the following highlighted 
protons. For each signal, its expected chemical shift, 
multiplicity, and integration are shown. 
 
 
 
 
15.20. GHB is expected to produce five signals in its 1H NMR spectrum. For each signal, its expected chemical shift, 
multiplicity, and integration are shown below. Note that OH protons typically do not couple with neighboring protons, 
and as a result, no splitting occurs. Furthermore, OH signals generally appear as broad singlets. 
 
O
O
O
H H
H H
H H
H
H
= ~12 ppm
m = singlet (broad)
I = 1H
= ~2-5 ppm
m = singlet (broad)
I = 1H
= 1.2 + 0.5 + 0.2 = 1.9 ppm
m = quintet, or triplet of triplets, depending on J values
I = 2H
= 1.2 + 2.5 = 3.7 ppm
m = triplet
I = 2H
= 1.2 + 1.0 = 2.2 ppm
m = triplet
I = 2H 
 
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