Question 1

Which of the following functional groups has the most deshielded proton and would be predicted to show an NMR signal that is the farthest downfield?

Accepted Answer

A)  benzylic - H 
B)  allylic - H 
C)  aldehyde - H 
D)  aromatic - H 
E)  acetylenic - H 
A)  benzylic - H 
B)  allylic - H 
C)  aldehyde - H 
D)  aromatic - H 
E)  acetylenic - H

Question 2

What compound exhibits three singlets in its proton spin decoupled 13C NMR spectrum?

Accepted Answer

A)  BrCH2CH2CH2Br 
B)  BrCH2CH2CH2Cl 
C)  (CH3)2CHCH(CH3)2 
D)  CH3CH2CH2CH3 
E)  (CH3)2CHOCH(CH3)2 
A)  BrCH2CH2CH2Br 
B)  BrCH2CH2CH2Cl 
C)  (CH3)2CHCH(CH3)2 
D)  CH3CH2CH2CH3 
E)  (CH3)2CHOCH(CH3)2

Question 3

Given that compound X has a molecular formula of C6H10O2, gave three peaks in its 13C NMR spectrum (14, 63 and 158 ppm) and two peaks in its 1H NMR spectrum (1.4, triplet and 4.3 ppm, quartet), provide a structure for compound X.

Accepted Answer

Question 4

The protons labeled Ha in the structure below generally show up as a triplet, even through there are three neighboring protons. The coupling constant is approximately 7 Hz. What does this suggest about the size of the coupling constant for the aldehydic proton?

Accepted Answer

It suggests that the

Question 5

What is the relationships between Ha and Hb in the following structure?

Accepted Answer

A)  homeotopic 
B)  enantiotopic 
C)  diastereotopic 
D)  none of the previous 
A)  homeotopic 
B)  enantiotopic 
C)  diastereotopic 
D)  none of the previous

Question 6

If a molecule contains 4 elements of unsaturation and signals in the 1H NMR spectrum between δ 7.0 and 8.0 ppm, what structural group is likely to be present?

Accepted Answer

A)  a carbonyl group 
B)  an aromatic ring 
C)  a hydroxyl group 
D)  a cyclohexyl ring 
E)  a carbon-carbon triple bond 
A)  a carbonyl group 
B)  an aromatic ring 
C)  a hydroxyl group 
D)  a cyclohexyl ring 
E)  a carbon-carbon triple bond

Question 7

Predict the number of signals expected (disregarding splitting) in the 1H NMR spectrum of the compound shown below.

Accepted Answer

Question 8

Deduce the identity of the following compound from the spectral data given.
C7H10O2: 1H NMR, δ 1.16 (3H, singlet), 2.21 (2H, singlet); 13C NMR, δ 216.25 (singlet), 52.57 (singlet), 34.51 (triplet), 20.22 (quartet) (ppm)

Accepted Answer

2,2-dimeth

Question 9

What multiplicities are observed for the signals in the off-resonance decoupled 13C spectrum of 2-chloropropene?

Accepted Answer

A)  3 singlets 
B)  2 singlets and a doublet 
C)  a singlet and 2 doublets 
D)  a singlet, a doublet and a triplet 
E)  a singlet, a triplet, and a quartet 
A)  3 singlets 
B)  2 singlets and a doublet 
C)  a singlet and 2 doublets 
D)  a singlet, a doublet and a triplet 
E)  a singlet, a triplet, and a quartet

Question 10

What are the relative integrations for the 1H NMR signals for the following compound?

Accepted Answer

A)  3:1:2:2 
B)  3:3:2 
C)  3:1:4 
D)  5:3 
A)  3:1:2:2 
B)  3:3:2 
C)  3:1:4 
D)  5:3

Which of the following functional groups has the most deshielded proton and would be predicted to show an NMR signal that is the farthest downfield?

What compound exhibits three singlets in its proton spin decoupled ¹³C NMR spectrum?

Given that compound X has a molecular formula of C₆H₁₀O₂, gave three peaks in its ¹³C NMR spectrum (14, 63 and 158 ppm) and two peaks in its ¹H NMR spectrum (1.4, triplet and 4.3 ppm, quartet), provide a structure for compound X.

The protons labeled Ha in the structure below generally show up as a triplet, even through there are three neighboring protons. The coupling constant is approximately 7 Hz. What does this suggest about the size of the coupling constant for the aldehydic proton?

What is the relationships between Ha and Hb in the following structure?

If a molecule contains 4 elements of unsaturation and signals in the ¹H NMR spectrum between δ 7.0 and 8.0 ppm, what structural group is likely to be present?

Predict the number of signals expected (disregarding splitting) in the ¹H NMR spectrum of the compound shown below.

Deduce the identity of the following compound from the spectral data given. C₇H₁₀O₂: ¹H NMR, δ 1.16 (3H, singlet), 2.21 (2H, singlet); ¹³C NMR, δ 216.25 (singlet), 52.57 (singlet), 34.51 (triplet), 20.22 (quartet) (ppm)

What multiplicities are observed for the signals in the off-resonance decoupled ¹³C spectrum of 2-chloropropene?

What are the relative integrations for the ¹H NMR signals for the following compound?

Structure and Bonding

Acids and Bases; Functional Groups

Structure and Stereochemistry of Alkanes

The Study of Chemical Reactions

Stereochemistry

Alkyl Halides; Nucleophilic Substitution

Structure and Synthesis of Alkenes; Elimination

Reactions of Alkenes

Structure and Synthesis of Alcohols

Reactions of Alcohols

Infrared Spectroscopy and Mass Spectrometry

Ethers, Epoxides, and Thioethers

Conjugated Systems, Orbital Symmetry, and Ultraviolet Spectroscopy

Aromatic Compounds

Reactions of Aromatic Compounds

Ketones and Aldehydes

Amines

Carboxylic Acids

Carboxylic Acid Derivatives

Condensations and Alpha Substitutions of Carboxyl Compounds

Carbohydrates and Nucleic Acids

Amino Acids, Peptides, and Proteins

Lipids

Synthetic Polymers

Filters

Exam 13: Nuclear Magnetic Resonance Spectroscopy

Which of the following functional groups has the most deshielded proton and would be predicted to show an NMR signal that is the farthest downfield?

What compound exhibits three singlets in its proton spin decoupled 13C NMR spectrum?

Given that compound X has a molecular formula of C6H10O2, gave three peaks in its 13C NMR spectrum (14, 63 and 158 ppm) and two peaks in its 1H NMR spectrum (1.4, triplet and 4.3 ppm, quartet), provide a structure for compound X.

The protons labeled Ha in the structure below generally show up as a triplet, even through there are three neighboring protons. The coupling constant is approximately 7 Hz. What does this suggest about the size of the coupling constant for the aldehydic proton?

What is the relationships between Ha and Hb in the following structure?

If a molecule contains 4 elements of unsaturation and signals in the 1H NMR spectrum between δ 7.0 and 8.0 ppm, what structural group is likely to be present?

Predict the number of signals expected (disregarding splitting) in the 1H NMR spectrum of the compound shown below.

Deduce the identity of the following compound from the spectral data given. C7H10O2: 1H NMR, δ 1.16 (3H, singlet), 2.21 (2H, singlet); 13C NMR, δ 216.25 (singlet), 52.57 (singlet), 34.51 (triplet), 20.22 (quartet) (ppm)

What multiplicities are observed for the signals in the off-resonance decoupled 13C spectrum of 2-chloropropene?

What are the relative integrations for the 1H NMR signals for the following compound?

Structure and Bonding

Acids and Bases; Functional Groups

Structure and Stereochemistry of Alkanes

The Study of Chemical Reactions

Stereochemistry

Alkyl Halides; Nucleophilic Substitution

Structure and Synthesis of Alkenes; Elimination

Reactions of Alkenes

Structure and Synthesis of Alcohols

Reactions of Alcohols

Infrared Spectroscopy and Mass Spectrometry

Ethers, Epoxides, and Thioethers

Conjugated Systems, Orbital Symmetry, and Ultraviolet Spectroscopy

Aromatic Compounds

Reactions of Aromatic Compounds

Ketones and Aldehydes

Amines

Carboxylic Acids

Carboxylic Acid Derivatives

Condensations and Alpha Substitutions of Carboxyl Compounds

Carbohydrates and Nucleic Acids

Amino Acids, Peptides, and Proteins

Lipids

Synthetic Polymers

Filters

What compound exhibits three singlets in its proton spin decoupled ¹³C NMR spectrum?

Given that compound X has a molecular formula of C₆H₁₀O₂, gave three peaks in its ¹³C NMR spectrum (14, 63 and 158 ppm) and two peaks in its ¹H NMR spectrum (1.4, triplet and 4.3 ppm, quartet), provide a structure for compound X.

If a molecule contains 4 elements of unsaturation and signals in the ¹H NMR spectrum between δ 7.0 and 8.0 ppm, what structural group is likely to be present?

Predict the number of signals expected (disregarding splitting) in the ¹H NMR spectrum of the compound shown below.

Deduce the identity of the following compound from the spectral data given. C₇H₁₀O₂: ¹H NMR, δ 1.16 (3H, singlet), 2.21 (2H, singlet); ¹³C NMR, δ 216.25 (singlet), 52.57 (singlet), 34.51 (triplet), 20.22 (quartet) (ppm)

What multiplicities are observed for the signals in the off-resonance decoupled ¹³C spectrum of 2-chloropropene?

What are the relative integrations for the ¹H NMR signals for the following compound?