Deck 25: Amines

Question 1

Arrange the following compounds in order of decreasing boiling point, putting the compound with the highest boiling point first. $$\mathrm { CH } _ { 3 } \mathrm { CH } _ { 2 } \mathrm { CH } _ { 2 } \mathrm { CH } _ { 2 } \mathrm { NH } _ { 2 } \quad \mathrm { CH } _ { 3 } \mathrm { CH } _ { 2 } \mathrm { OCH } _ { 2 } \mathrm { CH } _ { 3 } \quad \mathrm { CH } _ { 3 } \mathrm { CH } _ { 2 } \mathrm { CH } _ { 2 } \mathrm { CH } _ { 2 } \mathrm { OH }$$
$$\mathrm { I }\quad\quad\quad\quad\quad\quad\mathrm { II }\quad\quad\quad\quad\quad\quad\mathrm { III }$$

A) I > II > III
B) I > III > II
C) III > I > II
D) III > II > I

Answer 1

III > I > II

Question 2

What is the IUPAC name of the following compound?

A) N-ethyl-N-methylcyclopentanamine
B) N-cyclopentyl-N-methylethanamine
C) N-methyl-N-ethylcyclopentylamine
D) N-ethyl-N-methylpentanamine

Answer 2

N-ethyl-N-methylcyclopentanamine

Question 3

What is the common name of the following compound?

A) diisopropylamine
B) dipropylamine
C) diisopropanamine
D) dibutylamine

Answer 3

diisopropylamine

Question 4

What is the IUPAC name of the following compound?

A) N-ethyl-N-methylpentylamine
B) N-ethyl-N-methyl-1-pentanamine
C) N-methyl-3-octanamine
D) N-ethyl-2-heptanamine

Question 5

Which of the following amines are classified as tertiary (3°) amines?

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

Question 6

Which of the following amines are classified as secondary (2°) amines?

A) I
B) II
C) III
D) I and II

Question 7

What is the correct assignment of the names of the following aromatic amines?

A) I = pyrrolidine; II = pyrimidine; III = aniline.
B) I = pyrrole; II = pyrimidine; III = anisole.
C) I = pyrrolidine; II = pyridine; III =aniline.
D) I = pyrrole; II = pyridine; III = aniline.

Question 8

What is the IUPAC name of the following compound?

A) (Z)-4-hexen-1-amine
B) (E)-4-hexen-1-amine
C) (E)-2-hexen-6-amine
D) (Z)-2-hexen-6-amine

Question 9

Although an amine nitrogen atom containing an electron pair and bonded to three different groups is technically a stereogenic center, the chirality of the amine nitrogen is often ignored. Why is that?

A) Because four bonds are needed to define a stereogenic center.
B) Because chirality only exists with the tetrahedral carbon atoms.
C) Because there is usually slow interconversion between the two isomeric forms at room temperature.
D) Because there is usually rapid interconversion between the two isomeric forms at room temperature.

Question 10

What is the approximate bond angle of the substituents around a nitrogen atom in amines?

A) 90°
B) 109.5°
C) 120°
D) 180°

Question 11

What is the IUPAC name of the following compound?

A) 3-methyl-1-hexanamine
B) 4-methyl-1-hexylamine
C) 4-methyl-1-hexanamine
D) 3-methyl-6-hexylamine

Question 12

What is the IUPAC name of the following compound?

A) (S)-methyl-4-hexanamine
B) (S)-5-methyl-3-hexanamine
C) (R)-2-methyl-4-hexanamine
D) (R)-5-methyl-3-hexanamine

Question 13

What is the IUPAC name of the following compound?

A) 1-methyl-N-propyl-1-propanamine
B) 4-methyl-4-heptanamine
C) 2-propyl-3-hexanamine
D) N-propyl-2-pentanamine

Question 14

What is the common name of the following compound?

A) dimethylisobutylamine
B) butyldimethylamine
C) N,N-dimethylbutanamine
D) sec-butyldimethylamine

Question 15

What is the IUPAC name of the following compound?

A) N-propylhexanamine
B) N-propylaniline
C) N-ethylcyclohexylamine
D) N-propylcyclohexanamine

Question 16

Why should the chirality of an ammonium salt with four different groups on the nitrogen atom not be ignored?

A) Because there is rapid interconversion between the two isomeric forms at room temperature.
B) Because interconversion cannot occur between the two isomeric forms at room temperature.
C) Because the compound would be a meso compound.
D) Because the compound would be a racemic mixture.

Question 17

What is the common name of the following compound?

A) isopropylamine
B) 2-methyl-2-propanamine
C) tert-butylamine
D) isobutylamine

Question 18

What is the common name of the following compound?

A) isopropylamine
B) sec-butylamine
C) 2-methyl-1-propanamine
D) isobutylamine

Question 19

Which of the following amines are classified as primary (1°) amines?

A) I
B) II
C) III
D) I and II

Question 20

What is the common name of the following compound?

A) isopropylamine
B) sec-butylamine
C) isobutylamine
D) tert-butylamine

Question 21

Why is direct nucleophilic substitution of an alkyl halide with NH₃ not a very useful method for preparing primary amines?

A) NH₃ is not a nucleophile.
B) Elimination will occur.
C) NH₃ is too bulky to act as a nucleophile.
D) Polyalkylation of the amine will result in multiple products.

Question 22

What is the major organic product obtained in the following reaction?

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

Question 23

Predict the product(s) of the following reaction.

A) I
B) II
C) III
D) None of the choices

Question 24

Why are alkylamines more basic than arylamines?

A) The lone pair electrons are localized in alkylamines and delocalized in arylamines.
B) The lone pair electrons are delocalized in alkylamines and localized in arylamines.
C) The lone pair electrons are less readily available in alkylamines.
D) The lone pair electrons are more readily available in arylamines.

Question 25

The mass spectrum of an amine shows a parent peak with an odd mass for the molecular ion. What does this tell you about the amine?

A) The amine is a primary amine.
B) The amine is a secondary amine.
C) The amine contains an even number of N atoms.
D) The amine contains an odd number of N atoms.

Question 26

What is the major organic product obtained in the following reaction?

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

Question 27

Rank the following compounds in order of increasing basicity, putting the least basic compound first.

A) III < II < IV < I
B) II < III < IV < I
C) I < IV < II < III
D) III < I < II < IV

Question 28

Arrange the following amines in order of decreasing water solubility, putting the most soluble amine first.

A) I > II > III
B) II > I > III
C) III > I > II
D) II > III > I

Question 29

What is the major organic product obtained in the following reaction?

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

Question 30

What is the major organic product obtained in the following reaction?

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

Question 31

A compound with molecular formula C₆H₁₅N exhibits a singlet at  0.9 (1H), a triplet at  1.10 (3H), a singlet at  1.15 (9H), and a quartet at  2.6 (2H) in its ¹HNMR spectrum. Its IR spectrum shows one medium absorption band near 3400 cm^-1. What is the structure of this compound?

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

Question 32

In the preparation of primary amines, how can direct nucleophilic substitution between NH₃ and alkyl halide be made more practical than reacting NH₃ and the alkyl halide in a 1:1 ratio?

A) Use a large excess of NH₃.
B) Use a large excess of alkyl halide.
C) Use a limited amount of NH₃.
D) Make the alkyl halide sterically hindered.

Question 33

Rank the following compounds in order of increasing basicity, putting the least basic first. $$\begin{array} { c c c c } \mathrm { CH } _ { 3 } \mathrm { CONH } _ { 2 } & \mathrm { NH } _ { 3 } & \mathrm { CH } _ { 3 } \mathrm { CH } _ { 2 } \mathrm { NH } _ { 2 } & \left( \mathrm { CH } _ { 3 } \mathrm { CH } _ { 2 } \right) _ { 2 } \mathrm { NH } \\\text { I } & \text { II } & \text { III } & \text { IV }\end{array}$$

A) II < III < IV < I
B) I < II < III < IV
C) IV < III < II < I
D) II < I < III < IV

Question 34

Which of the following alkyl halides cannot be used to prepare primary amines by the Gabriel synthesis?

A) 2-bromo-2-methylbutane
B) 1-bromo-2-methylbutane
C) 2-bromo-3-methylbutane
D) 1-bromo-3-methylbutane

Question 35

Rank the following compounds in order of decreasing basicity, putting the most basic compound first.

A) II > I > III > IV
B) I > II > III > IV
C) I > III > II > IV
D) IV > II > III > I

Question 36

Arrange the following compounds in order of increasing boiling point, putting the compound with the least boiling point first.

A) I < II < III
B) II < I < III
C) I < III < II
D) II < III < I

Question 37

Why is the N-H bond of an imide especially acidic?

A) The conjugate base is stabilized by electron-donating inductive effect.
B) The conjugate base is stabilized by resonance.
C) The conjugate acid is stabilized by resonance.
D) The conjugate base is stabilized by intramolecular hydrogen bonding.

Question 38

Why are 1°, 2°, and 3° alkylamines more basic than ammonia (NH₃)?

A) Because of the electron-withdrawing inductive effect of the alkyl groups.
B) Because of the steric hindrance of the alkyl groups.
C) Because of the resonance delocalization of the alkyl groups.
D) Because of electron-donating inductive effect of the alkyl groups.

Question 39

What is a typical characteristic absorption in the IR spectrum of a primary amine?

A) Two N-H absorptions at 2500-2600 cm^-1
B) One N-H absorption at 2500-2600 cm^-1
C) Two N-H absorptions at 3300-3500 cm^-1
D) One N-H absorption at 3300-3500 cm^-1

Question 40

What is the name given to naturally occurring amines derived from plant sources?

A) Enamines
B) Imines
C) Alkaloids
D) Alkamines

Question 41

Predict the major product of the following reaction.

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

Question 42

Predict the major organic product of the following reaction.

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

Question 43

Select the reagent(s) required for the following transformation.

A) NaF
B) (1) NaNO₂, HCl; (2) F₂
C) (1) NaNO₂, HCl; (2) HBF₄
D) F₂

Question 44

Why is piperidine a stronger base than pyridine?

A) The lone pair of electrons in pyridine is part of the delocalized  system.
B) Aromatic compounds are always less basic than non-aromatic compounds.
C) The lone pair of electrons in piperidine is in an sp³ hybrid orbital; the lone pair of electrons in pyridine is in an sp hybrid orbital.
D) The lone pair of electrons in piperidine is in an sp³ hybrid orbital; the lone pair of electrons in pyridine is in an sp² hybrid orbital.

Question 45

Rank the nitrogen atoms in chloroquine, shown below, in order of decreasing basicity, putting the most basic nitrogen atom first.

A) N1 > N2 > N3
B) N2 > N1 > N3
C) N3 > N2 > N1
D) N3 > N1 > N2

Question 46

Predict the major organic product of the following reaction.

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

Question 47

Predict the major product of the following reaction.

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

Question 48

Why is pyrrole much less basic than pyridine?

A) The lone pair of electrons in pyrrole is located on an sp² orbital.
B) The lone pair of electrons in pyrrole is part of the aromatic  system.
C) The lone pair of electrons in pyrrole is not part of the aromatic  system.
D) The pK_a of the conjugate acid of pyrrole is much greater than the conjugate acid of pyridine.

Question 49

Rank the following compounds in order of decreasing basicity, putting the most basic first.

A) I > II > III > IV
B) I > III > II > IV
C) IV > III > I > II
D) II > I > III > IV

Question 50

Select the reagent(s) required for the following transformation.

A) NaI
B) (1) NaNO₂, HCl; (2) NaI
C) (1) NaNO₂, HCl; (2) I₂
D) I₂

Question 51

Rank the following compounds in increasing order of basicity, putting the least basic first.

A) II < I < IV < III
B) I < III < II < IV
C) IV < II < III < I
D) I < II < III < IV

Question 52

Histamine, a vasodilator, is responsible for a wide variety of physiological effects. Rank the three nitrogen atoms in histamine in increasing order of basicity, putting least basic nitrogen atom first.

A) N2 < N1 < N3
B) N1 < N2 < N3
C) N3 < N1 < N2
D) N3 < N2 < N1

Question 53

What starting materials are required to synthesize the following azo compound?

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

Question 54

Predict the major organic product of the following reaction.

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

Question 55

Select the reagent(s) required for the following transformation.

A) (1) NaNO₂, HCl; (2) H₂
B) (1) NaNO₂, HCl; (2) H₂O
C) (1) NaNO₂, HCl; (2) H₃PO₄
D) (1) NaNO₂, HCl; (2) H₃PO₂

Question 56

Predict the major product of the following reaction.

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

Question 57

Predict the major product of the following reaction.

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

Question 58

Predict the major organic product of the following reaction.

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