Question 1

What type of 2-D NMR spectrum indicates which carbon atoms are coupled to which hydrogen atoms?

Accepted Answer

A) DEPT 
B) APT 
C) COSY 
D) HETCOR 
E) MRI 
A) DEPT 
B) APT 
C) COSY 
D) HETCOR 
E) MRI

Question 2

An unknown compound, C3H5Cl3, gave the following proton NMR data:
Doublet at 1.70 ppm (3H)
Multiplet at 4.32 ppm (1H)
Doublet at 5.85 ppm (1H)
What is the structure of the compound?

Accepted Answer

Question 3

Provide the structure that is consistent with the data below.
C4H8O
IR (cm-1): 2950
1H NMR (δ): 3.5 (4H, d), 1.6 (1H, m), 1.0 (3H, d)
13C NMR (δ): 62 (t), 35 (d), 15 (q)

Accepted Answer

Question 4

How many signals would you expect to see in the 1H NMR spectrum of the following compound?

Accepted Answer

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

Question 5

Deduce the identity of the following compound from the 1H NMR spectral data given.
C3H3Cl5 : δ 4.5 (1H, triplet), 6.1 (2H, doublet)(ppm)

Accepted Answer

Question 6

Which of the following methyl groups will exhibit the most downfield (highest)chemical shift in 1H NMR spectroscopy?

Accepted Answer

A) I 
B) II 
C) III 
D) IV 
E) V 
A) I 
B) II 
C) III 
D) IV 
E) V

Question 7

Deduce the identity of the following compound from the spectral data given.
C4H6O2 : 1H NMR, δ 2.28 (2H, multiplet), 2.50 (2H, triplet), 4.35 (2H, triplet); 13C NMR, δ 177.81 (singlet), 68.58 (triplet), 27.70 (triplet), 22.17 (triplet)(ppm)

Accepted Answer

Question 8

H-H coupling is observed in the 1H NMR spectrum of CH3CH2OCH3 and the signal from the methylene H's does not appear as a single peak. How does this signal appear? Explain in detail what is occurring.

Accepted Answer

The methylene H's are perturbed by the n

Question 9

Provide the structure that is consistent with the data below.
C5H12O
IR (cm-1): 3200-3600 (broad), 2950
1H NMR (δ): 3.4 (2H, s), 2.9 (1H, broad s), 0.9 (9H, s)
13C NMR (δ): 64 (t), 39 (s), 14 (q)

Accepted Answer

Question 10

Predict the splitting pattern in the proton coupled 13C NMR spectrum for the following compound.

Accepted Answer

A) A, B, G = quartet; C, D, E, F = doublet 
B) A, B, G = triplet; C, D, E, F = singlet 
C) A, G = quintet; B = quartet; D, E = triplet; C, F = doublet 
D) A, G = triplet; B = doublet; D, E = singlet 
E) A, G = quartet; B = triplet; D, E = doublet; C, F = singlet 
A) A, B, G = quartet; C, D, E, F = doublet 
B) A, B, G = triplet; C, D, E, F = singlet 
C) A, G = quintet; B = quartet; D, E = triplet; C, F = doublet 
D) A, G = triplet; B = doublet; D, E = singlet 
E) A, G = quartet; B = triplet; D, E = doublet; C, F = singlet

Question 11

If two signals differ by 3 ppm, how do they differ in Hertz in a 60 MHz spectrometer?

Accepted Answer

A) 20 Hz 
B) 300 Hz 
C) 360 Hz 
D) 180 Hz 
E) 90 Hz 
A) 20 Hz 
B) 300 Hz 
C) 360 Hz 
D) 180 Hz 
E) 90 Hz

Question 12

Predict the number of signals expected, their splitting, and their relative area in the 1H NMR spectrum of 1,2-dichloroethane (ClCH2CH2Cl).

Accepted Answer

Question 13

Which of the following compounds has a signal disappear when D2O is added to it, ethyl alcohol or ethyl chloride?

Accepted Answer

The signal would dis

Question 14

What is indicated by a cross peak in the COSY spectrum of a compound?

Accepted Answer

The dots that are not on the d

Question 15

How many distinct triplets would you expect in the 1H NMR of the compound below?

Accepted Answer

A) 0 
B) 2 
C) 4 
D) 6 
E) 8 
A) 0 
B) 2 
C) 4 
D) 6 
E) 8

Question 16

Provide the structure that is consistent with the data below.
C6H11N
IR (cm-1): 2950, 2230
1H NMR (δ): 1.7 (quintet, 1H), 1.2 (m, 4H), 0.9 (t, 6H)
13C NMR (δ): 95 (s), 45 (d), 25 (t), 18 (q)

Accepted Answer

Question 17

What is the ratio of the protons in the following compound?

Accepted Answer

A) 3:3:2 
B) 3:2 
C) 6:2:1 
D) 3:1 
E) 3:2:1 
A) 3:3:2 
B) 3:2 
C) 6:2:1 
D) 3:1 
E) 3:2:1

Question 18

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

Accepted Answer

3 signals: (3H, trip

Question 19

Give the structure of a compound that has a formula of C5H10O2, and has a triplet (3H, 1.1 ppm), sextet (2H, 1.8 ppm), triplet (2H, 2.3 ppm)and a singlet (3H, 3.8 ppm)in the 1H NMR spectrum.

Accepted Answer

A)    
B)    
C)    
D)    
E)    
A)    
B)    
C)    
D)    
E)

Question 20

Deduce the identity of the compound from the data provided. C7H12: IR (cm-1): 3300, 2950, 2220; 13C NMR: 5 signals

Accepted Answer

A) 1,2-dimethylcyclopentene 
B) 5-methyl-2-hexyne 
C) 3,3-dimethyl-1-pentyne 
D) 4,4-dimethyl-1-pentyne 
E) 2,4-dimethyl-2-pentene 
A) 1,2-dimethylcyclopentene 
B) 5-methyl-2-hexyne 
C) 3,3-dimethyl-1-pentyne 
D) 4,4-dimethyl-1-pentyne 
E) 2,4-dimethyl-2-pentene

Exam 15: Nmr Spectroscopy

What type of 2-D NMR spectrum indicates which carbon atoms are coupled to which hydrogen atoms?

An unknown compound, C3H5Cl3, gave the following proton NMR data: Doublet at 1.70 ppm (3H) Multiplet at 4.32 ppm (1H) Doublet at 5.85 ppm (1H) What is the structure of the compound?

Provide the structure that is consistent with the data below. C4H8O IR (cm-1): 2950 1H NMR (δ): 3.5 (4H, d), 1.6 (1H, m), 1.0 (3H, d) 13C NMR (δ): 62 (t), 35 (d), 15 (q)

How many signals would you expect to see in the 1H NMR spectrum of the following compound?

Deduce the identity of the following compound from the 1H NMR spectral data given. C3H3Cl5 : δ 4.5 (1H, triplet), 6.1 (2H, doublet)(ppm)

Which of the following methyl groups will exhibit the most downfield (highest)chemical shift in 1H NMR spectroscopy?

Deduce the identity of the following compound from the spectral data given. C4H6O2 : 1H NMR, δ 2.28 (2H, multiplet), 2.50 (2H, triplet), 4.35 (2H, triplet); 13C NMR, δ 177.81 (singlet), 68.58 (triplet), 27.70 (triplet), 22.17 (triplet)(ppm)

H-H coupling is observed in the 1H NMR spectrum of CH3CH2OCH3 and the signal from the methylene H's does not appear as a single peak. How does this signal appear? Explain in detail what is occurring.

Provide the structure that is consistent with the data below. C5H12O IR (cm-1): 3200-3600 (broad), 2950 1H NMR (δ): 3.4 (2H, s), 2.9 (1H, broad s), 0.9 (9H, s) 13C NMR (δ): 64 (t), 39 (s), 14 (q)

Predict the splitting pattern in the proton coupled 13C NMR spectrum for the following compound.

If two signals differ by 3 ppm, how do they differ in Hertz in a 60 MHz spectrometer?

Predict the number of signals expected, their splitting, and their relative area in the 1H NMR spectrum of 1,2-dichloroethane (ClCH2CH2Cl).

Which of the following compounds has a signal disappear when D2O is added to it, ethyl alcohol or ethyl chloride?

What is indicated by a cross peak in the COSY spectrum of a compound?

How many distinct triplets would you expect in the 1H NMR of the compound below?

Provide the structure that is consistent with the data below. C6H11N IR (cm-1): 2950, 2230 1H NMR (δ): 1.7 (quintet, 1H), 1.2 (m, 4H), 0.9 (t, 6H) 13C NMR (δ): 95 (s), 45 (d), 25 (t), 18 (q)

What is the ratio of the protons in the following compound?

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

Give the structure of a compound that has a formula of C5H10O2, and has a triplet (3H, 1.1 ppm), sextet (2H, 1.8 ppm), triplet (2H, 2.3 ppm)and a singlet (3H, 3.8 ppm)in the 1H NMR spectrum.

Deduce the identity of the compound from the data provided. C7H12: IR (cm-1): 3300, 2950, 2220; 13C NMR: 5 signals

Remembering General Chemistry: Electronic Structure and Bonding

Acids and Bases: Central to Understanding Organic Chemistry

An Introduction to Organic Compounds

Isomers: the Arrangement of Atoms in Space

Alkenes Thermodynamics and Kinetics

Reactions of Alkenes

Reactions of Alkynes Introduction to Multistep Synthesis

Electron Delocalization, Resonance, and Aromaticity More About Molecular Orbital Theory

Substitution Reactions of Alkyl Halides

Elimination Reactions of Alkyl Halides Competition Between Substitution and Elimination

Reactions of Alcohols, Ethers, Epoxides, and Sulfur-Containing Compounds

Organometallic Compounds

Reactions of Alkanes, Radicals

Mass Spectrometry, Infrared Spectroscopy, and Uvvis Spectroscopy

Reactions of Carboxylic Acids and Carboxylic Acid Derivatives

Reactions of Aldehydes and Ketones

Reactions at the Alpha Carbon of Carbonyl Compounds

Reactions of Benzene and Substituted Benzenes

More About Amines Heterocylic Compounds

Carbohydrates

Amino Acids, Peptides, and Proteins

Catalysis

The Organic Mechanisms of the Coenzymes

The Chemistry of Metabolism

Nucleosides, Nucleotides, and Nucleic Acids

Synthetic Polymers

Pericyclic Reactions

Filters

An unknown compound, C₃H₅Cl₃, gave the following proton NMR data: Doublet at 1.70 ppm (3H) Multiplet at 4.32 ppm (1H) Doublet at 5.85 ppm (1H) What is the structure of the compound?

Provide the structure that is consistent with the data below. C₄H₈O IR (cm^-1): 2950 ¹H NMR (δ): 3.5 (4H, d), 1.6 (1H, m), 1.0 (3H, d) ¹³C NMR (δ): 62 (t), 35 (d), 15 (q)

How many signals would you expect to see in the ¹H NMR spectrum of the following compound?

Deduce the identity of the following compound from the ¹H NMR spectral data given. C₃H₃Cl₅ : δ 4.5 (1H, triplet), 6.1 (2H, doublet)(ppm)

Which of the following methyl groups will exhibit the most downfield (highest)chemical shift in ¹H NMR spectroscopy?

Deduce the identity of the following compound from the spectral data given. C₄H₆O₂ : ¹H NMR, δ 2.28 (2H, multiplet), 2.50 (2H, triplet), 4.35 (2H, triplet); ¹³C NMR, δ 177.81 (singlet), 68.58 (triplet), 27.70 (triplet), 22.17 (triplet)(ppm)

H-H coupling is observed in the ¹H NMR spectrum of CH₃CH₂OCH₃ and the signal from the methylene H's does not appear as a single peak. How does this signal appear? Explain in detail what is occurring.

Provide the structure that is consistent with the data below. C₅H₁₂O IR (cm^-1): 3200-3600 (broad), 2950 ¹H NMR (δ): 3.4 (2H, s), 2.9 (1H, broad s), 0.9 (9H, s) ¹³C NMR (δ): 64 (t), 39 (s), 14 (q)

Predict the splitting pattern in the proton coupled ¹³C NMR spectrum for the following compound.

Predict the number of signals expected, their splitting, and their relative area in the ¹H NMR spectrum of 1,2-dichloroethane (ClCH₂CH₂Cl).

Which of the following compounds has a signal disappear when D₂O is added to it, ethyl alcohol or ethyl chloride?

How many distinct triplets would you expect in the ¹H NMR of the compound below?

Provide the structure that is consistent with the data below. C₆H₁₁N IR (cm^-1): 2950, 2230 ¹H NMR (δ): 1.7 (quintet, 1H), 1.2 (m, 4H), 0.9 (t, 6H) ¹³C NMR (δ): 95 (s), 45 (d), 25 (t), 18 (q)

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

Give the structure of a compound that has a formula of C₅H₁₀O_2, and has a triplet (3H, 1.1 ppm), sextet (2H, 1.8 ppm), triplet (2H, 2.3 ppm)and a singlet (3H, 3.8 ppm)in the ¹H NMR spectrum.

Deduce the identity of the compound from the data provided. C₇H₁₂: IR (cm^-1): 3300, 2950, 2220; ¹³C NMR: 5 signals