Question 1

Deduce the identity of the following compound from the 1H NMR data given.
C6H10O2: δ 2.19 (3H, singlet), 2.70 (2H, singlet) (ppm)

Accepted Answer

CH₃COCH₂CH₂COCH₃

Question 2

How many nuclear spin states are allowed for the 1H nucleus?

Accepted Answer

A)  1 
B)  2 
C)  3 
D)  4 
E)  10 
A)  1 
B)  2 
C)  3 
D)  4 
E)  10 B

Question 3

Predict the number of signals expected, their splitting, and their relative area in the 1H NMR spectrum of CH3CH2OCH3.

Accepted Answer

3 signals: (3H, triplet); (2H, quartet); (3H, singlet)

Question 4

How might the proton spectrum of ultrapure dimethylamine, (CH3)2NH, differ from the spectrum of this compound to which D2O has been added?

Accepted Answer

N-H signal will broa

Question 5

Provide a structure that is consistent with the data below.
C9H9N
IR (cm-1): 3050, 2950, 2240, 1630
1H NMR ( d): 7.5 (2H, d), 7.1 (2H, d), 2.3 (2H, q), 0.9 (3H, t)
13C NMR (d ): 137 (s), 130, (s), 126 (d), 122 (d), 95 (s), 25 (t), 15 (q)

Accepted Answer

Question 6

Predict the number of signals expected in the proton spin decoupled 13C spectrum of   
(1,3-dichlorobenzene).

Accepted Answer

Question 7

Provide a structure that is consistent with the data below.
C4H8O
IR (cm-1): 2950
1H NMR ( d): 3.2 (4H, t), 1.2 (4H, t)
13C NMR (d ): 68 (t), 27 (t)

Accepted Answer

Question 8

Deduce the identity of the following compound from the 1H NMR data given.
C7H7NO3: δ 3.9 (3H, singlet), 6.9 (2H, doublet), 8.1 (2H, doublet) (ppm)

Accepted Answer

p-nitroani

Question 9

Why is Fourier transform NMR spectroscopy preferred over continuous wave as a technique for

Accepted Answer

¹³C nuclei have a low sensitivity which re

Question 10

Predict the number of signals expected, their splitting, and their relative area in the 1H NMR spectrum of (CH3)3CCHO.

Accepted Answer

2 signals:

Question 11

1H nuclei located near electronegative atoms tend to be ________ relative to 1H nuclei which are not.

Accepted Answer

A)  shielded 
B)  deshielded 
C)  resonanced 
D)  split 
E)  none of the above 
A)  shielded 
B)  deshielded 
C)  resonanced 
D)  split 
E)  none of the above

Question 12

What type of carbon environment does not generate a signal in the DEPT-90 spectrum and gives a positive peak in the DEPT-135 spectrum?

Accepted Answer

A)  quaternary 
B)  methine 
C)  methylene 
D)  methyl 
E)  carbonyl 
A)  quaternary 
B)  methine 
C)  methylene 
D)  methyl 
E)  carbonyl

Question 13

Predict the number of distinct quartets expected in the off-resonance decoupled   
spectrum of the compound shown below.

Accepted Answer

The answer of Predict the number of distinct quartets expected...

Question 14

What is the expected multiplicity and relative ratio of the area of the peak for the protons labeled Ha?

Accepted Answer

A)  singlet with relative area of 1 
B)  triplet with relative area of 1:1:1 
C)  triplet with relative area of 1:3:1 
D)  multiplet with relative area of 1:6:15:20:15:6:1 
A)  singlet with relative area of 1 
B)  triplet with relative area of 1:1:1 
C)  triplet with relative area of 1:3:1 
D)  multiplet with relative area of 1:6:15:20:15:6:1

Question 15

Provide a structure that is consistent with the data below.
C5H8Cl2
IR (cm-1): 2950
1H NMR ( d): 1.4 (4H, t), 1.2 (4H, t)
13C NMR (d ): 62 (s), 26 (t), 23 (t)

Accepted Answer

Question 16

Provide a structure that is consistent with the data below.
C9H7Cl
IR (cm-1): 3050, 2950, 2220, 1620
1H NMR ( d): 7.8 (2H, d), 7.2 (2H, d), 2.1 (3H, s)
13C NMR (d ): 140 (s), 132, (s), 125 (d), 122 (d), 88 (s), 83 (s), 18 (q)

Accepted Answer

Question 17

How might the two trimethylcyclohexane isomers shown below be most readily distinguished using NMR?

Accepted Answer

Number of

Question 18

Given that compound X has a molecular formula of C6H8O2, gave two peaks in its 13C NMR spectrum (37 ppm and 208 ppm) but just one in its 1H NMR spectrum (2.5 ppm), provide a structure for compound X.

Accepted Answer

Question 19

Predict the number of signals expected in the proton spin decoupled 13C NMR spectrum of the compound shown below.

Accepted Answer

Question 20

Deduce the identity of the following compound from the 13C NMR data given.
C9H12: δ 21.3 (quartet), 127.2 (doublet), 138.0 (singlet) (ppm)

Accepted Answer

1,3,5-trim

Exam 13: Nuclear Magnetic Resonance Spectroscopy

Deduce the identity of the following compound from the 1H NMR data given. C6H10O2: δ 2.19 (3H, singlet), 2.70 (2H, singlet) (ppm)

How many nuclear spin states are allowed for the 1H nucleus?

Predict the number of signals expected, their splitting, and their relative area in the 1H NMR spectrum of CH3CH2OCH3.

How might the proton spectrum of ultrapure dimethylamine, (CH3)2NH, differ from the spectrum of this compound to which D2O has been added?

Provide a structure that is consistent with the data below. C9H9N IR (cm-1): 3050, 2950, 2240, 1630 1H NMR ( d): 7.5 (2H, d), 7.1 (2H, d), 2.3 (2H, q), 0.9 (3H, t) 13C NMR (d ): 137 (s), 130, (s), 126 (d), 122 (d), 95 (s), 25 (t), 15 (q)

Predict the number of signals expected in the proton spin decoupled 13C spectrum of (1,3-dichlorobenzene).

Provide a structure that is consistent with the data below. C4H8O IR (cm-1): 2950 1H NMR ( d): 3.2 (4H, t), 1.2 (4H, t) 13C NMR (d ): 68 (t), 27 (t)

Deduce the identity of the following compound from the 1H NMR data given. C7H7NO3: δ 3.9 (3H, singlet), 6.9 (2H, doublet), 8.1 (2H, doublet) (ppm)

Why is Fourier transform NMR spectroscopy preferred over continuous wave as a technique for

Predict the number of signals expected, their splitting, and their relative area in the 1H NMR spectrum of (CH3)3CCHO.

1H nuclei located near electronegative atoms tend to be ________ relative to 1H nuclei which are not.

What type of carbon environment does not generate a signal in the DEPT-90 spectrum and gives a positive peak in the DEPT-135 spectrum?

Predict the number of distinct quartets expected in the off-resonance decoupled spectrum of the compound shown below.

What is the expected multiplicity and relative ratio of the area of the peak for the protons labeled Ha?

Provide a structure that is consistent with the data below. C5H8Cl2 IR (cm-1): 2950 1H NMR ( d): 1.4 (4H, t), 1.2 (4H, t) 13C NMR (d ): 62 (s), 26 (t), 23 (t)

Provide a structure that is consistent with the data below. C9H7Cl IR (cm-1): 3050, 2950, 2220, 1620 1H NMR ( d): 7.8 (2H, d), 7.2 (2H, d), 2.1 (3H, s) 13C NMR (d ): 140 (s), 132, (s), 125 (d), 122 (d), 88 (s), 83 (s), 18 (q)

How might the two trimethylcyclohexane isomers shown below be most readily distinguished using NMR?

Given that compound X has a molecular formula of C6H8O2, gave two peaks in its 13C NMR spectrum (37 ppm and 208 ppm) but just one in its 1H NMR spectrum (2.5 ppm), provide a structure for compound X.

Predict the number of signals expected in the proton spin decoupled 13C NMR spectrum of the compound shown below.

Deduce the identity of the following compound from the 13C NMR data given. C9H12: δ 21.3 (quartet), 127.2 (doublet), 138.0 (singlet) (ppm)

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Structure and Stereochemistry of Alkanes

The Study of Chemical Reactions

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Alkyl Halides; Nucleophilic Substitution

Structure and Synthesis of Alkenes; Elimination

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Reactions of Alcohols

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Deduce the identity of the following compound from the ¹H NMR data given. C₆H₁₀O₂: δ 2.19 (3H, singlet), 2.70 (2H, singlet) (ppm)

How many nuclear spin states are allowed for the ¹H nucleus?

Predict the number of signals expected, their splitting, and their relative area in the ¹H NMR spectrum of CH₃CH₂OCH₃.

How might the proton spectrum of ultrapure dimethylamine, (CH₃)₂NH, differ from the spectrum of this compound to which D₂O has been added?

Provide a structure that is consistent with the data below. C₉H₉N IR (cm^-1): 3050, 2950, 2240, 1630 ¹H NMR ( d): 7.5 (2H, d), 7.1 (2H, d), 2.3 (2H, q), 0.9 (3H, t) ¹³C NMR (d ): 137 (s), 130, (s), 126 (d), 122 (d), 95 (s), 25 (t), 15 (q)

Predict the number of signals expected in the proton spin decoupled ¹³C spectrum of (1,3-dichlorobenzene).

Provide a structure that is consistent with the data below. C₄H₈O IR (cm^-1): 2950 ¹H NMR ( d): 3.2 (4H, t), 1.2 (4H, t) ¹³C NMR (d ): 68 (t), 27 (t)

Deduce the identity of the following compound from the ¹H NMR data given. C₇H₇NO₃: δ 3.9 (3H, singlet), 6.9 (2H, doublet), 8.1 (2H, doublet) (ppm)

Predict the number of signals expected, their splitting, and their relative area in the ¹H NMR spectrum of (CH₃)₃CCHO.

¹H nuclei located near electronegative atoms tend to be ________ relative to ¹H nuclei which are not.

Provide a structure that is consistent with the data below. C₅H₈Cl₂ IR (cm^-1): 2950 ¹H NMR ( d): 1.4 (4H, t), 1.2 (4H, t) ¹³C NMR (d ): 62 (s), 26 (t), 23 (t)

Provide a structure that is consistent with the data below. C₉H₇Cl IR (cm^-1): 3050, 2950, 2220, 1620 ¹H NMR ( d): 7.8 (2H, d), 7.2 (2H, d), 2.1 (3H, s) ¹³C NMR (d ): 140 (s), 132, (s), 125 (d), 122 (d), 88 (s), 83 (s), 18 (q)

Given that compound X has a molecular formula of C₆H₈O₂, gave two peaks in its ¹³C NMR spectrum (37 ppm and 208 ppm) but just one in its ¹H NMR spectrum (2.5 ppm), provide a structure for compound X.

Predict the number of signals expected in the proton spin decoupled ¹³C NMR spectrum of the compound shown below.

Deduce the identity of the following compound from the ¹³C NMR data given. C₉H₁₂: δ 21.3 (quartet), 127.2 (doublet), 138.0 (singlet) (ppm)