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Solutions for Nuclear Magnetic Resonance Spectroscopy
BrCH3
H CH3
CH3H
ba
c
ba
a = δ 7.1 (singlet, 2H)
b = δ 2.3 (singlet, 6H)
c = δ 2.2 (singlet, 3H) BrCH3
H3C H
HH3C
A second structure is also possible although it is 
less likely because the Br would probably 
deshield the Hs labeled "a" to about 7.3–7.4.
a
a
b
b
c
CH3 CH2 CCl2 CH3
CH3 CH
CH3
OH CH CH3
CH3
CH3
CH3H
H H
HH
O
CH3
2
(All of these benzene H atoms
are accidentally equivalent
and do not split each other.)
1
1
10
2
(assume OH exchanging 
rapidly—no splitting)
1
2
7
143
(f)(d)
(c)(b)(a)
34 The numbers in italics indicate the number of peaks in each signal. Approximate chemical shift values 
are in bold.
33 continued
H
H
H
CH3 O CH2 CH2 CH2Cl
CH3 CH2 C C H
CH3 CH2 C
O
CH3
35 Consult Appendix 1 in the text for chemical shift values. Your predictions should be in the given 
range, or within 0.5-1.0 ppm of the given value.
(a) (b)
(c) (d)
(e) (f)
all at δ 7.2 all at δ 1.3
δ 3.4 δ 3.8
δ 1.6
δ 3.2
δ 1.2 δ 2.2 δ 2.5
δ 1.0 δ 2.5 δ 2.0
δ 0.9
δ 4.3
δ 3.8
δ 2-5
CH O
CH3
CH3
CH2 CH2 OH
δ 3.8
CH CHCH3 C
O
HC
O
H
(g) (h)
δ 1.7
δ 6-7
δ 5-6 δ 9-10δ 9-10
HH
H
δ 8.0
δ 8.0
δ 7.5
The C=O has its strongest deshielding 
effect at the adjacent H (ortho) and 
across the ring (para). The remaining 
H (meta) is less deshielded.
(e) CH3 CH2 C O
O
CH2 CH3
3 34
H
6
1.0 2.2 1.7
4.0
1.2
2-5 0.9
1.4
2.3
7.2
1.0 4.0 1.2
4.2
1.2
306