Question 1

Which statement best explains why tertiary amines have lower boiling points than primary and secondary amines of similar molecular weight?

Accepted Answer

Tertiary amines cannot form hydrogen bonds due to the absence of N—H bonds.

Question 2

Which of the following compounds is classified as a quaternary ammonium salt?

Accepted Answer

$$\mathrm{(CH_3$)_4N^+Cl^-}$$

Question 3

Amines are generally more basic than ammonia because:

Accepted Answer

Alkyl groups stabilize the ammonium ion, making the nitrogen more basic.

Question 4

Which IR spectral feature would you expect for a primary amine?

Accepted Answer

Two N—H stretches between 3200 and 3500 $$\mathrm{cm$$^{-1}$$}$$

Question 5

Which of the following statements about the chirality of amines is correct?

Accepted Answer

Chiral quaternary ammonium salts can be resolved into enantiomers because nitrogen inversion is not possible.

Question 6

Which of the following best describes the effect of resonance on the basicity of aromatic amines?

Accepted Answer

Resonance delocalization of the nitrogen lone pair decreases basicity.

Question 7

Which of the following is the correct IUPAC name for the compound $$\mathrm{CH_3CH_2CH_2NH_2}$$?

Accepted Answer

Propan-1-amine

Question 8

A student attempts to synthesize a primary amine by alkylation of ammonia with an alkyl halide. What is a major problem with this method?

Accepted Answer

Multiple alkylations occur, leading to a mixture of products.

Question 9

Which of the following statements about the Hofmann elimination is correct?

Accepted Answer

The least substituted alkene is the major product (Hofmann product).

Question 10

Which of the following is true regarding the solubility of amines in water?

Accepted Answer

Small amines (fewer than six carbons) are generally soluble in water.

Question 11

Which of the following best explains why pyrrole is a very weak base?

Accepted Answer

Protonation of pyrrole nitrogen destroys aromatic stabilization.

Question 12

Which method is most commonly used to synthesize secondary amines via reductive amination?

Accepted Answer

Condensation of a ketone or aldehyde with a primary amine, followed by reduction of the imine.

Question 13

Which of the following statements about the Gabriel synthesis is correct?

Accepted Answer

It uses phthalimide as a nucleophile to prepare primary amines.

Question 14

Which of the following is a biologically active amine that acts as a neurotransmitter?

Accepted Answer

Dopamine

Question 15

What is the major product when a tertiary amine is oxidized with hydrogen peroxide?

Accepted Answer

Amine oxide

Question 16

Which of the following statements about mass spectrometry of amines is correct?

Accepted Answer

The molecular ion of a compound with an odd number of nitrogen atoms has an odd mass number.

Question 17

Which of the following is true about the formation of sulfonamides?

Accepted Answer

Sulfonyl chlorides react with primary or secondary amines to form sulfonamides.

Question 18

Which of the following best describes the mechanism of acylation of amines?

Accepted Answer

Nucleophilic acyl substitution

Question 19

Which of the following statements about the Sandmeyer reaction is correct?

Accepted Answer

It converts an aromatic amine into a diazonium salt, which can then be transformed into various functional groups.

Amines: Structure, Properties, Synthesis, and Reactions (Chapter 19 Study Notes)

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