problems ch 18. 2 learning check give the common and iupac names, and classify each as primary,...

PROBLEMS CH 18

2

Learning CheckGive the common and IUPAC names, and classify each as primary,secondary, or tertiary.

3

SolutionA.

STEP 1 Name the longest carbon chain bonded to the NSTEP 1 atoms as alkanamines by replacing e of theSTEP 1 alkane name with amine.

STEP 2 Number the carbon chain to show the position ofSTEP 2 the amine group and any substituents.

CH3—CH2 —CH2—NH2

Propylamine (common), 1°

1-Propanamine (IUPAC)

3 2 1

Propanamine

4

Solution (continued)

ethanamine

B.

STEP 1 Name the longest carbon chain bonded to the NSTEP 1 atoms as alkanamines by replacing e of theSTEP 1 alkane name with amine.

STEP 2 Number the carbon chain to show the position ofSTEP 2 the amine group and any substituents.

5

Solution (continued)B.

STEP 3 In a secondary or tertiary amine, use the prefixSTEP 3 N- to name groups attached to the N atom.

Ethyldimethylamine (common),

N,N-Dimethylethanamine (IUPAC), 3°

6

Learning CheckDraw the condensed structural formula for each of the following:

A. 2-pentanamine

B. N-methyl-1-butanamine

7

Solution

CH3—CH2—CH2—CH2—NH—CH3

Draw the condensed structural formula for each ofthe following:

A. 2-pentanamine

B. N-methyl-1-butanamine

8

Learning Check Give the common and IUPAC names for each of the following:

A.

B.

C.

NH2

9

Solution

Ethylmethylamine(common); N-methylethanamine

A.

B.

C.

NH2

Butylethylmethylamine (common);N-ethyl-N-methyl-1-butanamine

Aniline

10

Classification of Amines Amines are classified as primary, secondary, or tertiary.

In a primary (1) amine, one carbon group is bonded to the nitrogen atom.

A secondary (2) amine has two carbon groups.

A tertiary (3) amine has three carbon groups.

11

Learning Check

Consider the following compounds:1) CH3—CH2—CH2—NH2

2) CH3—CH2—NH—CH3

3) CH3—CH2—CH2—CH3

A. Which compound has the highest boiling point?

B. Which compound(s) is/are soluble in water?

12

Solution

Consider the following compounds:1) CH3—CH2—CH2—NH2

2) CH3—CH2—NH—CH3

3) CH3—CH2—CH2—CH3

A. Which compound has the highest boiling point?1) CH3—CH2—CH2—NH2

B. Which compound(s) is/are soluble in water?1) CH3—CH2—CH2—NH2

2) CH3—CH2—NH—CH3

13

Learning Check

Identify the following heterocyclic amines: A. B. C.

N

H

N

H

N

H

14

Solution

Identify the following heterocyclic amines: A. B. C.

Piperidine Pyrrolidine Pyrrole

N

H

N

H

N

H

15

Learning Check

Identify the heterocyclic amine in serotonin.

16

Solution

The heterocyclic amine in serotonin is pyrrole.

17

Write the IUPAC name for

STEP 1 Determine the alkane name of the carbon chain in the carboxyl portion and replace e with amide.

butanamide STEP 2 Name each substituent on the N atom using the prefix N- and the alkyl name.

N-ethylbutanamide

IUPAC Names of Amides

N-Methylethanamide (IUPAC)N-Methylacetamide (common)

N-Ethylpropanamide (IUPAC)N-Ethylpropionamide (common)

18

CH3—C H2—C—N—CH2—CH3

O║

H—

Examples of IUPAC and Common Names

19

CH3—CH2—CH2—CH2—C—N—CH2—CH3

O║

CH2—CH3│

Learning Check

Write the IUPAC name for the following:

STEP 1 Determine the alkane name of the carbon chain in the carboxyl portion and replace e with amide.

pentanamide STEP 2 Name each substituent on the N atom using the prefix N- and the alkyl name.

N,N-diethylpentanamide

20

Solution

21

Learning Check

Draw the condensed structural formulas of the following amides.

A. pentanamide

B. N-methylbutyramide

Draw the condensed structural formulas of the following amides.

A. pentanamide

B. N-methylbutyramide

22

Solution

Give the common and IUPAC names for the followingamides, and classify them as primary, secondary, or tertiary.

A.

B.

23

Learning Check

Give the common and IUPAC names for the followingamides, and classify them as primary, secondary, or tertiary.

A.

B.

24

Butryamide (common)butanamide (IUPAC)primary (1)

N-ethyl-N-methylethanamide (IUPAC), tertiary

N-Ethyl-N-methylacetamide (common) (3)

Solution