1. Match the following to their IR spectra
H
O
(30 points)
OH
O
O O
OH
b
a
1466
2941
c
3333
1716
3026 1650
d 1450
1685
3034
3341
3086
e
f 2820
2766 1703
2817 2966
2716 1731
1617
1. Circle the structure of the product that corresponds to the 1H NMR and IR data below. Circle only one structure N C
N C
Br
NO2
O
NO2
N C
Br
Br
NO2
Br
Br
Br
Br O
Br
Br
O OMe
O O OMe
1H
NMR
IR
MeO
O
8.07 ppm (d, J=7.9 Hz, 2H) 7.32 ppm (d, J=7.9 Hz, 2H) 2.35 ppm (s, 3H)
3109 1596
1512 1353
4000
3000
2000
1500
1000
500
2. Circle the structure of the product that corresponds to the 1H NMR and IR data below. Circle only one structure N C
N C
Br
NO2
O
NO2
N C
Br
Br
NO2
Br
Br
Br
Br O
Br
Br
O OMe
O O OMe
1H
NMR
MeO
O
7.22 ppm (d, J=7.9 Hz, 2H) 7.45 ppm (d, J=7.9 Hz, 2H) 2.41 ppm (s, 3H)
IR
2229
4000
3000
2000
1609 1509
1500
1000
500
3. Circle the structure of the product that corresponds to the 1H NMR and IR data below. Circle only one structure N C
N C
Br
NO2
O
NO2
N C
Br
Br
NO2
Br
Br
Br
Br O
Br
Br
O OMe
O O OMe
1H
NMR
8.17 7.96 7.67 7.31 3.91
MeO
O
ppm (t, J=2.1 Hz, 1H) (dt, J=8.0, 2.1 Hz, 1H) (dt, J=7.7,2.1 Hz, 1H) (dd, J=8.0, 7.7 Hz, 1H) ppm (s, 3H)
IR
1571 1436
1729
4000
3000
2000
1500
1000
500
1. Match the following to their IR spectra
HO
(24 points) (not all compounds have a match)
O O Cl
O
CN
OH
b
a
2120 1585 1603 1689
3301 4000
3000
2000
1500
1000
500
4000
3000
2000
1500
1000
500
1500
1000
500
d c 2249
1716 4000
3000
2000
1500
1000
500 4000
3000
2000
(24 points) (not all compounds have a match) 1. Match the following to their IR spectra O CN
NO2
O
O
O
b
a
1374 1552
1670 4000
3000
2000
1500
1000
500
4000
3000
2000
1500
1000
500
1500
1000
500
d c 1776 4000
3000
1750 2000
1500
1000
500 4000
3000
2000
Name______________________________________
2. Calculate the UV maximum for the following compounds. (20 points)
O OAc
O Br
O
Name______________________________________
3. Explain how the labeled fragments are formed. Relative intensities are given in parentheses. (20 points)
180 (95) 181(100)
N
77 (58)
H MW = 181 104 (14)
182 (13)
Name______________________________________
4. The mass spectra of compounds A and B are nearly identical, except for the additional peak at 208 in the spectrum of A. Explain why, and in doing so assign the labeled peaks in the mass spectrum. (20 points) O O
180 MW=208
A
152 208
180
O
MW=180 B
152
Name______________________________________
5. McLafferty rearrangements of the molecules depicted below will give rise to fragments that can be detected by mass spectrometry. Circle the fragments that are observed. You may need to circle more than one answer for each! (24 points)
O D D
120
121
122
120
121
122
120
121
122
120
121
122
120
121
122
120
121
122
O D H
O D
D
O D
H
O D D
O D H O
D
D
120
121
122
O
D
H
120
121
122
2. C9H13NO 13
C NMR 138.6, s 129.1, d (2) 128.3, d (2) 126.3, d 66.2, t 54.1, d 40.8, t
1
H NMR 7.40–7.22, m, 5H 5.2 broad s, 1H (exchanges with D2O) 3.69, dd, 1H, J = 11 and 3 Hz 3.45, dd, 1 H, J = 11 and 6 Hz 3.17, m, 1H 2.86, dd, 1H, J=12 and 4 Hz 2.58, dd, 1 HJ = 12 and 8 Hz 2.1, broad s, 2H
MS: 151 (M+, 92), 134 (3), 120 (100), 103 (22), 91 (40), 77 (12), 65 (9), 60 (90), 42 (9), 30 (4), 28 (2) IR:
1
H NMR
J = 11 Hz
2. (continued) To receive full credit for question 2, clearly show your rationale for elucidating the structure. In addition, all 1H and 13C NMR chemical shifts, as well as 1H coupling constants must be assigned and displayed in the designated blocks. This will involve drawing your final structure at least 3 times. Furthermore, assign at least 2 peaks associated with the main functional groups in the IR spectrum. Also, assign the bolded numbers in the mass spectrum. Simply drawing the structure of the product will get you no credit.
13
C chemical shift assignments
1
H Chemical shift assignments
1
H coupling constant assignments
