Question 1

A prominent (M 1+ $\bullet$ -18)peak suggests that the compound might be a(n):

Accepted Answer

A)  Alkane 
B)  Alcohol 
C)  Ether 
D)  Ketone 
E)  Primary amine 
A)  Alkane 
B)  Alcohol 
C)  Ether 
D)  Ketone 
E)  Primary amine D

Question 2

Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s)indicated with the arrow?

Accepted Answer

A)  3.00 ppm,doublet 
B)  3.00 ppm,triplet 
C)  5.00 ppm,triplet 
D)  1.00 ppm,doublet 
E)  3.00 ppm,singlet 
A)  3.00 ppm,doublet 
B)  3.00 ppm,triplet 
C)  5.00 ppm,triplet 
D)  1.00 ppm,doublet 
E)  3.00 ppm,singlet C

Question 3

Determine the most likely structure of a compound,with the molecular formula C9H12,which gave a 1H NMR spectrum consisting of: a doublet at  $\delta$1.25
A septet at  $\delta$2.90 and
A multiplet at  $\delta$7.25   ]

Accepted Answer

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

Question 4

What is the structure of the compound in the following 1H-NMR spectrum with the molecular formula C9H14O? IR data shows no characteristic peak around 1700 cm-1.The 13C-NMR chemical shifts (ppm): 108.4,50.9,31.6,23.5,2.0.Relative integration is known.

Accepted Answer

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

Question 5

A compound with the molecular formula C6H15N gave the following 1H NMR spectrum: triplet,$\delta$  0.90
Quartet,$\delta$  2.4
There were no other signals.The most likely structure for the compound is:

Accepted Answer

A) 
  
B) 
  
C)  CH3CH2CH2CH2CH2CH2NH2 
D) 
  
E) 
  
A) 
  
B) 
  
C)  CH3CH2CH2CH2CH2CH2NH2 
D) 
  
E)

Question 6

The data below from the molecular ion region of the mass spectrum of a halogen-containing compound are consistent with the presence of what halogen(s)in the original compound? intensity
M + $\bullet$ 
51)0
M + $\bullet$ +2
100)0
M + $\bullet$ +4
49)0

Accepted Answer

A)  One Br 
B)  One Cl 
C)  One Br and one Cl 
D)  Two Br 
E)  Two Cl 
A)  One Br 
B)  One Cl 
C)  One Br and one Cl 
D)  Two Br 
E)  Two Cl

Question 7

For the C2 methylene group in 1-bromopropane,the theoretical multiplicity in the 1H NMR spectrum,presuming that Jab is sufficiently different from Jbc and that the instrument has sufficient resolving power,is which of these?

Accepted Answer

A)  2 
B)  5 
C)  6 
D)  8 
E)  12 
A)  2 
B)  5 
C)  6 
D)  8 
E)  12

Question 8

What is the structure of the compound in the following 1H-NMR spectrum with the molecular formula C6H12O2? Relative integration is shown.

Accepted Answer

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

Question 9

How many 13C signals would you expect from anisole?

Accepted Answer

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

Question 10

Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s)indicated with the arrow?

Accepted Answer

A)  1.00 ppm,quartet 
B)  2.40 ppm,singlet 
C)  2.40 ppm,quartet 
D)  3.00 ppm,quartet 
E)  2.40 ppm,triplet 
A)  1.00 ppm,quartet 
B)  2.40 ppm,singlet 
C)  2.40 ppm,quartet 
D)  3.00 ppm,quartet 
E)  2.40 ppm,triplet

Question 11

What is the structure of the compound in the following 1H-NMR spectrum with the molecular formula C7H12O4? The 13C-NMR spectrum shows peaks at 14.1,40.8,61.0 and 166.8 ppm.Relative integration is shown.

Accepted Answer

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

Question 12

The 1H NMR spectrum of which of the compounds below,all of formula C7H12O2,would consist of three singlets only?

Accepted Answer

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

Question 13

What is the structure of the compound in the following 1H-NMR spectrum with the molecular formula C5H8O? The IR spectrum does show a characteristic stretch around 1700 cm-1.Relative integration is shown.

Accepted Answer

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

Question 14

-Which is the base peak?

Accepted Answer

A)  15 
B)  29 
C)  44 
D)  45 
E)  100 
A)  15 
B)  29 
C)  44 
D)  45 
E)  100

Question 15

How many 13C signals would 1,4-dimethylbenzene give?

Accepted Answer

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

Question 16

-Which is the likely molecular ion (M - $\bullet$ )?

Accepted Answer

A)  15 
B)  29 
C)  44 
D)  45 
E)  100 
A)  15 
B)  29 
C)  44 
D)  45 
E)  100

Question 17

What is the structure of the compound in the following 1H-NMR spectrum with the molecular formula C6H11N? In the IR spectrum you notice a stretch at about 2250 cm-1.Relative integration is shown.

Accepted Answer

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

Question 18

The C7 compound which gives 3 signals in the broadband proton-decoupled 13C spectrum could be:

Accepted Answer

A)  Heptane 
B)  2-Methylhexane 
C)  3,3-Dimethylpentane 
D)  2,4-Dimethylpentane 
E)  2,2,3-Trimethylbutane 
A)  Heptane 
B)  2-Methylhexane 
C)  3,3-Dimethylpentane 
D)  2,4-Dimethylpentane 
E)  2,2,3-Trimethylbutane

Question 19

A compound with the molecular formula C4H10O gives a 1H NMR spectrum consisting only of a quartet centered at  $\delta$3.5 and a triplet at  $\delta$1.1.The most likely structure for the compound is:

Accepted Answer

A) 
  
B) 
  
C)  CH3CH2CH2CH2OH 
D)  CH3CH2OCH2CH3 
E) 
  
A) 
  
B) 
  
C)  CH3CH2CH2CH2OH 
D)  CH3CH2OCH2CH3 
E)

Question 20

What is the structure of the compound in the following 1H-NMR spectrum with the molecular formula C6H10O2? Relative integration is shown.

Accepted Answer

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

Exam 9: Nuclear Magnetic Resonance and Mass Spectrometry: Tools for Structure Determination

A prominent (M 1+ ∙\bullet∙ -18)peak suggests that the compound might be a(n):

Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s)indicated with the arrow?

Determine the most likely structure of a compound,with the molecular formula C9H12,which gave a 1H NMR spectrum consisting of: a doublet at δ\deltaδ 1.25 A septet at δ\deltaδ 2.90 and A multiplet at δ\deltaδ 7.25 ]

What is the structure of the compound in the following 1H-NMR spectrum with the molecular formula C9H14O? IR data shows no characteristic peak around 1700 cm-1.The 13C-NMR chemical shifts (ppm): 108.4,50.9,31.6,23.5,2.0.Relative integration is known.

A compound with the molecular formula C6H15N gave the following 1H NMR spectrum: triplet, δ\deltaδ 0.90 Quartet, δ\deltaδ 2.4 There were no other signals.The most likely structure for the compound is:

The data below from the molecular ion region of the mass spectrum of a halogen-containing compound are consistent with the presence of what halogen(s)in the original compound? intensity M + ∙\bullet∙ 51)0 M + ∙\bullet∙ +2 100)0 M + ∙\bullet∙ +4 49)0

For the C2 methylene group in 1-bromopropane,the theoretical multiplicity in the 1H NMR spectrum,presuming that Jab is sufficiently different from Jbc and that the instrument has sufficient resolving power,is which of these?

What is the structure of the compound in the following 1H-NMR spectrum with the molecular formula C6H12O2? Relative integration is shown.

How many 13C signals would you expect from anisole?

Which one of the following best represents the predicted approximate chemical shift and coupling for the hydrogen(s)indicated with the arrow?

What is the structure of the compound in the following 1H-NMR spectrum with the molecular formula C7H12O4? The 13C-NMR spectrum shows peaks at 14.1,40.8,61.0 and 166.8 ppm.Relative integration is shown.

The 1H NMR spectrum of which of the compounds below,all of formula C7H12O2,would consist of three singlets only?

What is the structure of the compound in the following 1H-NMR spectrum with the molecular formula C5H8O? The IR spectrum does show a characteristic stretch around 1700 cm-1.Relative integration is shown.

-Which is the base peak?

How many 13C signals would 1,4-dimethylbenzene give?

-Which is the likely molecular ion (M - ∙\bullet∙ )?

What is the structure of the compound in the following 1H-NMR spectrum with the molecular formula C6H11N? In the IR spectrum you notice a stretch at about 2250 cm-1.Relative integration is shown.

The C7 compound which gives 3 signals in the broadband proton-decoupled 13C spectrum could be:

A compound with the molecular formula C4H10O gives a 1H NMR spectrum consisting only of a quartet centered at δ\deltaδ 3.5 and a triplet at δ\deltaδ 1.1.The most likely structure for the compound is:

What is the structure of the compound in the following 1H-NMR spectrum with the molecular formula C6H10O2? Relative integration is shown.

Carbon Compounds and Chemical Bonds

Representative Carbon Compounds: Functional Groups, Intermolecular Forces, and Infrared Ir Spectroscopy

An Introduction to Organic Reactions: Acids and Bases

Alkanes: Nomenclature, Conformational Analysis, and an Introduction to Synthesis

Stereochemistry: Chiral Molecules

Ionic Reactions - Nucleophilic Substitution and Elimination Reactions of Alkyl Halides

Alkenes and Alkynes I: Properties and Synthesis, Elimination Reactions of Alkyl Halides

Alkenes and Alkynes Ii: Addition Reactions

Radical Reactions

Alcohols and Ethers

Alcohols From Carbonyl Compounds Oxidation-Reduction and Organometallic Compounds

Conjugated Unsaturated Systems

Aromatic Compounds

Reactions of Aromatic Compounds

Aldehydes and Ketones I Nucleophilic Addition to the Carbonyl Group

Aldehydes and Ketones Ii Aldol Reactions

Carboxylic Acids and Their Derivatives Nucleophilic Addition - Elimination at the Acyl Carbon

Synthesis and Reactions of Beta-Dicarbonyl Compounds: More Chemistry of Enolate Ions

Amines

Phenols and Aryl Halides: Nucleophilic Aromatic Substitution

Carbohydrates

Lipids

Amino Acids and Proteins

Nucleic Acids and Protein Synthesis

Filters

A prominent (M 1⁺ _$\bullet$ -18)peak suggests that the compound might be a(n):

What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₉H₁₄O? IR data shows no characteristic peak around 1700 cm^-1.The ¹³C-NMR chemical shifts (ppm): 108.4,50.9,31.6,23.5,2.0.Relative integration is known.

A compound with the molecular formula C₆H₁₅N gave the following ¹H NMR spectrum: triplet, $\delta$ 0.90 Quartet, $\delta$ 2.4 There were no other signals.The most likely structure for the compound is:

The data below from the molecular ion region of the mass spectrum of a halogen-containing compound are consistent with the presence of what halogen(s)in the original compound? intensity M ⁺ _$\bullet$ 51)0 M ⁺ _$\bullet$ +2 100)0 M ⁺ _$\bullet$ +4 49)0

For the C2 methylene group in 1-bromopropane,the theoretical multiplicity in the ¹H NMR spectrum,presuming that J_ab is sufficiently different from J_bc and that the instrument has sufficient resolving power,is which of these?

What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₆H₁₂O₂? Relative integration is shown.

How many ¹³C signals would you expect from anisole?

What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₇H₁₂O₄? The ¹³C-NMR spectrum shows peaks at 14.1,40.8,61.0 and 166.8 ppm.Relative integration is shown.

The ¹H NMR spectrum of which of the compounds below,all of formula C₇H₁₂O₂,would consist of three singlets only?

What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₅H₈O? The IR spectrum does show a characteristic stretch around 1700 cm^-1.Relative integration is shown.

How many ¹³C signals would 1,4-dimethylbenzene give?

$-Which is the likely molecular ion (M <sup>-</sup> <sub> \bullet </sub> )?$ -Which is the likely molecular ion (M ^- _$\bullet$ )?

What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₆H₁₁N? In the IR spectrum you notice a stretch at about 2250 cm^-1.Relative integration is shown.

The C₇ compound which gives 3 signals in the broadband proton-decoupled ¹³C spectrum could be:

A compound with the molecular formula C₄H₁₀O gives a ¹H NMR spectrum consisting only of a quartet centered at $\delta$ 3.5 and a triplet at $\delta$ 1.1.The most likely structure for the compound is:

What is the structure of the compound in the following ¹H-NMR spectrum with the molecular formula C₆H₁₀O₂? Relative integration is shown.