Chapter 10 - Amines

Multiple Choice

Section: 10.1Difficulty Level: Easy1. Which is the classification of the following amine?

a) 1°b) 2°c) 3°d) 4°

Section: 10.1Difficulty Level: Medium2. Procaine is a local anesthetic drug. What is the classification of the amines I and II?

NH2

ON

O

procaine

I

II

a) I: primary aliphatic; II: primary aromaticb) I: tertiary aliphatic, II: primary aromaticc) I: tertiary aliphatic, II: tertiary aromaticd) I: tertiary aromatic, II: tertiary aliphatic

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Chapter 10 - Amines

Section: 10.1Difficulty Level: Medium3. Dopamine is a neurotransmitter occurring in a wide variety of animals, including both vertebrates and invertebrates. What is the classification of the amine?

NH2HO

HO

dopamine

a) primary aromaticb) primary aliphaticc) secondary aromaticd) tertiary aliphatic

Section: 10.1Difficulty Level: Medium4. Hydrocodone is a semi-synthetic opioid, which is an orally active narcotic analgesic (painkiller), often found (together with acetaminophen (N-(4-hydroxyphenyl)acetamide)) in Vicodin and other brands. What is the classification of the amine?

OO

O

N

hydroconea) tertiary aromaticb) tertiary aliphaticc) secondary aliphaticd) primary aliphatic

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Chapter 10 - Amines

Section: 10.2Difficulty Level: Easy5. Which is the correct structure for diphenylamine?

NH2

N

H

NH2

CH2

NH2

I II

III IVa) Ib) IIc) IIId) IV

Section: 10.2Difficulty Level: Easy6. Which is the IUPAC name for the following structure?

a) N-methyl-tert-butylamineb) N-methyl-1,1-dimethylethylaminec) N-methyl-2-methyl-2-propanamined) tert-butyl methyl amine

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Chapter 10 - Amines

Section: 10.2Difficulty Level: Easy7. Which is the structure for N,N-dimethyl-3-hexanamine?

I II

III IV

NN

N N

a) Ib) IIc) IIId) IV

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Chapter 10 - Amines

Section: 10.2Difficulty Level: Medium8. Which pairs of names and structures match correctly?

NH

NH

NH

NH2

N

I. piperidine

II. pyrrole

III. cyclohexylamine

IV. prrolidine

V. pyridine

a) I and II and IIIb) II and IV and IVc) II and IV and Vd) I and III and V

Section: 10.2Difficulty Level: Medium9. Which is the name for the following compound?

a) aniline hydrochlorideb) phenyltrihydrogenammonium chloridec) aniline chlorided) benzylammonium chloride

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Chapter 10 - Amines

Section: 10.2Difficulty Level: Medium10. Which is the name for the following compound?

a) 4-carboxy anilineb) 1-amino-4-carboxybenzenec) benzylamine carboxylic acidd) 4-aminobenzoic acid

Section: 10.3Difficulty Level: Hard11. Arrange the amines in order of increasing boiling point (lowest first).

a) II, III, I, IVb) III, I, IV, IIc) IV, II, III, Id) IV, III, I, II

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Chapter 10 - Amines

Section: 10.3Difficulty Level: Hard12. Arrange the amines in order of increasing boiling point (lowest first).

NH2 NH2 NH2 NH2

FF

F

I II III IV

a) I, III, II, IVb) II, IV, I, IIIc) IV, II, III, Id) II, III, IV, I

Section: 10.3Difficulty Level: Medium13. Arrange the amines in order of increasing boiling point (lowest first).

methylamine ethylamine propylamine cyclohexylamine I II III IV

a) IV, III, II, Ib) I, II, III, IVc) III, II, I, IVd) II, I, IV, III

Section: 10.3Difficulty Level: Medium14. Arrange the amines in order of increasing solubility in water (least first).

a) II, III, I, IVb) IV, II, III, Ic) IV, III, II, Id) I, III, II, IV

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Chapter 10 - Amines

Section: 10.3Difficulty Level: Medium15. Arrange the amines in order of increasing solubility in water (least first).

I II

III IV

HN H

N

HN

HN

Cl Cl Cl

Cl

a) III, I, IV, IIb) II, I, III, IVc) I, III, IV, IId) IV, II, III, I

Section: 10.3Difficulty Level: Medium16. Arrange the following in order of increasing strength of the hydrogen bonds (weakest first).

a) I, II, III, IVb) II, I, IV, IIIc) II, IV, I, IIId) I, IV, II, III

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Chapter 10 - Amines

Section: 10.3Difficulty Level: Hard17. Arrange the basicities of the four amines in decreasing order (highest first).

NH2 NH2

NH

I II III IV

N

a) II, III, I, IVb) IV, III, II, Ic) I, III, IV, IId) III, IV, I, II

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Chapter 10 - Amines

Section: 10.3Difficulty Level: Hard18. Order the following bases according to increasing basicity (weakest base first):

HN

HN

HN

HN

I II

III IV

Cl

F

F

a) I, III, II, IVb) III, II, IV, Ic) IV, II, III, Id) II, IV, I, III

Section: 10.4Difficulty Level: Medium19. Which compound is the strongest base?

I II III IV

CH3 NH2 CH3 NH

CH3

CH3 N

CH3

CH3 CH3 N OH

CH3

a) Ib) IIc) IIId) IV

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Chapter 10 - Amines

Section: 10.4Difficulty Level: Medium20. Which compound is the strongest base?

NH2 NH2 NH2 NH2

Br NO2 CH3

I II III IVa) Ib) IIc) IIId) IV

Section: 10.4Difficulty Level: Medium21. Arrange the amines in order of increasing basicity (weakest first).

a) IV, II, III, Ib) II, I, III, IVc) I, II, III, IVd) II, I, IV, III

Section: 10.4Difficulty Level: Hard22. At pH 5.0, the ratio of morpholine and morpholinium ion is 1:1622. Which is the pKb of morpholine?

a) 3.21b) 5.79c) 8.21d) 9.25

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Chapter 10 - Amines

Section: 10.4Difficulty Level: Hard23. Guanidine has a pKb value of 0.4. Which is the ratio of guanidine to its conjugate acid at blood pH of 7.4?

a) 10-6.2:1b) 10+6.2:1c) 1:1d) 2.5:1

Section: 10.4Difficulty Level: Hard24. When the following compounds are dissolved in water at the same concentrations, which one will have the lowest pH (i.e., most acidic)?

CH2 N CH3

CH3

CH2 N CH3

CH3

CH3

OH

CH2 N CH3

CH3

Cl CH2 N CH3

CH3

CH3

Cl

H

I II

III IVa) Ib) IIc) IIId) IV

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Chapter 10 - Amines

Section: 10.5Difficulty Level: Medium25. Which are the correct positions for the site of protonation of the bases, guanidine and imidazole?

a) I, IIIb) II, IVc) I, IVd) II, III

Section: 10.5Difficulty Level: Medium26. The following mixture was extracted with 1 M HCl, followed by 1 M NaOH, followed by ether. Which compound is recovered from the acid solution?

a) Ib) IIc) IIId) None of the above

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Chapter 10 - Amines

Section: 10.5Difficulty Level: Medium27. Which reactions will proceed predominately to products as written?

a) I, IIb) III, IVc) II, IVd) I, III

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Chapter 10 - Amines

Section: 10.6Difficulty Level: Easy28. Which is the product of the following reaction?

NO2

CH3 CH3

Fe, HCl

ethanol/water

NO2

HOOC COOH

NH3+ Cl-

CH3 CH3

CH3 CH3

NO2

CH3 CH3

ClCl

I II

III IVa) Ib) IIc) IIId) IV

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Chapter 10 - Amines

Section: 10.7Difficulty Level: Medium29. Which is the product of the following reaction?

NH2

I II III

NH2

HCl/water 0oC

CH3

NO2O2N

CH3 CH3 CH3

N

N

CH3

O2N NO2

NH2Cl

IV

NaNO2

a) Ib) IIc) IIId) IV

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Chapter 10 - Amines

Section: 10.7Difficulty Level: Medium30. Trinitrotoluene (TNT) reacts with large quantities of hydrogen in the presence of a nickel catalyst. Which reaction product is formed?

NO2

NO2

O2NH2 / Ni

H2O

NO2

NO2

O2N NH2

NH2

H2N

NH2

NH2

H2N

I II

IIIIV

a) Ib) IIc) IIId) IV

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Chapter 10 - Amines

Section: 10.7Difficulty Level: Hard31. Adenosine reacts with sodium nitrite (food additive, for instance in bacon) in acidic aqueous solution. The loss of dinitrogen (N2) is observed. What is the main structure formed in this reaction?

OH

OH

HO

O

NN

H2N

N N

adenosine

NaNO2 / H+

H2O

OH

OHHO

O

NN

H2N

N N OH

OHHO

O

NN

HO

N N

OH

OHHO

O

NN

H

N N OH

OHHO

O

NN

O

HN N

NO2

I II

III IV

a) Ib) IIc) IIId) IV

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Chapter 10 - Amines

Section: 10.7Difficulty Level: Hard32. Which of the starting materials forms a stable product with the molecular formula C9H11N after a) hydrogenation with H2/Ni and b) a subsequent SN2-reaction (loss is HBr)? (10.7, HARD)

I II

III IV

NO2

Br Br

NO2

NO2

Br

NO2

Br

a) Ib) IIc) IIId) IV

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Chapter 10 - Amines

Section: 10.7Difficulty Level: Hard33. Which is the product of the following reaction?

NH2

I II III

NH2

HCl/water 0oC

CH3

CH3 CH3 CH3

CH3

IV

NaNO2

NH3+Cl-

O2P PO2

HPO2

NO2

a) Ib) IIc) IIId) IV

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Chapter 10 - Amines

Section: 10.1Difficulty Level: Medium34. Which structures are secondary amines?

a) I, IIb) II, IIIc) III, IVd) II, IV

Fill in the Blank Questions

Section: 10.2Difficulty Level: Easy1. The name of the following compound is ______________________________.

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Chapter 10 - Amines

Section: 10.2Difficulty Level: Medium2. The name of the following compound is _________________________________.

Section: 10.2Difficulty Level: Medium3. The name of the following compound is _______________________________.

Section: 10.4Difficulty Level: Medium4. The order of decreasing basicity of the following amines is (1 is the most basic),

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Chapter 10 - Amines

Section: 10.4Difficulty Level: Medium5. The order of increasing basicity of the following compounds is (1 is the least basic),

Section: 10.4Difficulty Level: Medium6. The order of increasing boiling point of the following compounds is (1 is lowest boiling),

Section: 10.6Difficulty Level: Medium7. The starting material needed to complete the following reaction is,

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Chapter 10 - Amines

Section: 10.7Difficulty Level: Medium8. The starting material needed to complete the following reaction is,

Section: 10.7Difficulty Level: Medium9. The major product of the following reaction is,

Section: 10.7Difficulty Level: Medium10. The reactants and solvents needed to complete the following reaction are?

O

NO2

O

NN

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Chapter 10 - Amines

Section: 10.7Difficulty Level: Medium11. The reactants and solvents needed to complete the following reaction are?

N

Cl

N

ClCl

Section: 10.7Difficulty Level: Hard12. The reactants needed to complete the following reaction are,

True-False Questions

Section: 10.1Difficulty Level: Easy1. Cyclohexanamine is a 2º amine.

Section: 10.1Difficulty Level: Easy2. tert-butyl methyl amine is a 3º amine.

Section: 10.2Difficulty Level: Easy3. The name of the following compound is N-cyclopentylethanamine.

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Chapter 10 - Amines

Section: 10.2Difficulty Level: Medium4. The name of the following compound is 3,5-dimethylpiperidine.

Section: 10.4Difficulty Level: Easy5. The strongest base in the following group is aniline.

Section: 10.4Difficulty Level: Medium6. The strongest base in the following group is methylthiocyclohexane.

Section: 10.4Difficulty Level: Medium7. The pKa for ethyl ammonium ion is 10.8 (ethyl amine pKb is 3.2).

Section: 10.4Difficulty Level: Medium8. Tertiary amines are generally stronger bases than secondary amines.

Section: 10.5Difficulty Level: Medium9. The equilibrium for the reaction of p-nitroaniline and acetic acid lies to the right.

Section: 10.7Difficulty Level: Easy10. The diazotization of amines with NaNO2 requires a basic aqueous medium.

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Chapter 10 - Amines

Section: 10.7Difficulty Level: Medium11. The reaction of aniline with nitrous acid after warming yields phenol.

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Chapter 10 - Amines

Answers

Multiple Choice

1. d2. b3. b4. b5. b6. c7. b8. d9. a10. d11. a The boiling points are I 89°C, II 17°C, III 56°C, and IV > 200oC (ionic solid).12. d 13. b14. d15. b16. b17. a18. c19. b20. d21. c22. b23. a24. c25. a26. a27. c28. b29. c30. b31. b32. a33. c34. d

Fill in the Blank Questions

1. 3-bromopiperidine

2. 3-methylbenzenediazonium chloride

3. N-methyl 2-methylcyclohexanamine

4. 4, 3, 2, 1

5. 1, 3, 4, 2

6. 1, 3, 2, 4

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Chapter 10 - Amines

7.

8.

9.

10.

O

NO2

O

NH2

O

NN

H2 / Ni

H2O H2O

NaNO2 / HCl

Cl

11.

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Chapter 10 - Amines

N

Cl

N

ClH2O

H3PO2 / HCl

Cl

12.

True-False Questions

1. F2. F3. F4. T5. F6. F7. T8. F9. F10. F11. T

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