Chapter 18–1
Chapter 18 Amines and Neurotransmitters
Solutions to In-Chapter Problems
18.1 To determine whether an amine is 1o, 2o, or 3o, count the number of carbons bonded to the nitrogen
atom as in Example 18.1. A 1o amine has one C–N bond, and so forth.
1o
2o
2o
1o
3o
C6H5
a.
H2N(CH2)3NH(CH2)4NH(CH2)3NH2
b.
CH3CH2O
C
N
CH3
O
18.2 Label the amine and hydroxyl group in scopolamine, a drug used to treat motion sickness, as 1o, 2o,
or 3o as in Example 18.1.
CH3
3° amine
1° hydroxyl group
N
O
CH2OH
O C CH
O
scopolamine
18.3 Methamphetamine is a 2° amine. Give the molecular shape around each atom by counting groups.
CH3
a. 2° amine
b.
CH2CHNHCH3
(1)
3 groups
trigonal
planar
(3)
3 atoms
1 lone pair
trigonal
(2)
4 groups pyramidal
tetrahedral
18.4 Name each amine as in Example 18.2.
2
a.
CH3CH2CHCH3
Answer: 2-butanamine
CH3CH2CHCH3
NH2
NH2
butane
(4 C's)
1
butanamine
1
b.
CH3CH2CH2 NHCH3
propane
3 C's
propanamine
CH3CH2CH2 NHCH3
Answer: N-methyl-1-propanamine
N-methyl
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Amines and Neurotransmitters 18–2
c.
N(CH3)2
N(CH3)2
6 C's in the ring
cyclohexanamine
Answer: N,N-dimethylcyclohexanamine
N,N-dimethyl
d. (CH3CH2CH2CH2)2NH
Answer: dibutylamine
2 butyl groups
(4 C's)
18.5 Work backwards to draw the structure corresponding to each name.
a. N-methylaniline
c. 3,5-diethylaniline
NHCH3
CH3CH2 5
N-methyl
1 NH2
3
CH2CH3
3,5-diethyl
d. N,N-diethylaniline
b. m-ethylaniline
N
CH2CH3
N,N-diethyl
CH3CH2
NH2
CH2CH3
m-ethyl
18.6 Work backwards to draw the structure corresponding to each name.
a. 3-hexanamine NH
2
e. N,N-dimethylethylamine
CH3CH2CHCH2CH2CH3
CH3CH2NCH3
CH3
3
b. N-methylpentylamine
!f. 2-aminocyclohexanone
CH3CH2CH2CH2CH2 NHCH3
O2N
2 NH2
2-amino
g. 1-propylcyclohexanamine
CH2CH2CH3
NH2
1
p-nitro
d. N-methylpiperidine
1-propyl
NH2
h. N-propylaniline
H
N
N
N-methyl
O
1
N-methyl
c. p-nitroaniline
N,N-dimethyl
CH3
CH2CH2CH3
N-propyl
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Chapter 18–3
18.7 Determine the compound in each pair with a higher boiling point, using the rules in Example 18.3.
O
a.
CH3
C
or
CH2CH3
(CH3)2CHCH2NH2
a 1o amine with N–H bonds
intermolecular hydrogen bonding
higher boiling point
a ketone with only C–H bonds
b.
or
(CH3)2CHCH2NH2
(CH3)2CHCH2OH
a 1o amine with N–H bonds
intermolecular hydrogen bonding
c.
a 1o alcohol with an O–H bond
intermolecular hydrogen bonding
stronger intermolecular forces
higher boiling point
or
NH2
CH3
a 1o amine with N–H bonds
intermolecular hydrogen bonding
higher boiling point
hydrocarbon
18.8 Caffeine is soluble in the organic solvent CH2Cl2 because caffeine is organic and “like dissolves
like.”
18.9 Nicotine has two heterocycles: pyridine and pyrrolidine.
pyridine
pyrrolidine
N
N
CH3
18.10 Draw both enantiomers of nicotine.
chirality center
H
H
N
N
N
N
CH3
CH3
N
N
CH3
enantiomers
18.11 Morphine contains a 3° amine.
HO
O
N
HO
CH3
N is bonded to three groups:
3° amine.
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Amines and Neurotransmitters 18–4
18.12 Identify the functional groups in heroin.
ester
CH3
O
C
aromatic ring
O
ether
O
O
C
CH3
3o amine
N
CH3
O
alkene
ester
18.13 Quinine has 11 trigonal planar carbon atoms [part (a), labeled with *] and nine tetrahedral carbon
atoms [part (b), all other C’s].
*
*
CH2=CH
HO
CH3O
*
*
*
*
*
N
CH
*
* N
quinine
*
*
18.14 Draw the products when the amines are treated with HCl as in Example 18.4.
HCl
a. CH3CH2NH2
HCl
b. (CH3CH2)2NH
+
(CH3CH3NH3) + Cl–
+
(CH3CH2)2NH2
+
HCl
c. (CH3CH2)3N
(CH3CH2)3NH
+
+ Cl–
Cl–
18.15 Draw the products of each reaction.
a.
CH3CH2CH2CH2 NH2
b.
(CH3)2NH
+
(CH3CH2CH2CH2
HCl
+
NH3)
+
Cl–
+
+
(CH3)2NH2
C6H5COOH
+
C6H5COO–
+
c.
+
N
H
+
H2O
OH–
N
H
H
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Chapter 18–5
18.16 Draw the products of the reaction.
HO
+
HO
H2SO4
OH
CHCH2NHCH3
HO
OH
+
CHCH2NH2CH3
HO
HSO4–
18.17 Name each ammonium salt as in Example 18.5.
a.
(CH3NH3)
b. [(CH3CH2CH2)2NH2] Br–
Cl–
chloride
derived from methylamine
c. [(CH3)2NHCH2CH3]
acetate
derived from ethyldimethylamine
bromide
derived from dipropylamine
methylammonium chloride
CH3COO–
dipropylammonium bromide
ethyldimethylammonium acetate
18.18 Ammonium salts are water-soluble solids. A water-insoluble amine can be converted to a watersoluble ammonium salt by treatment with acid.
a. (CH3CH2)3N
b.
[(CH3CH2)3NH] Br–
3° amine with 6 C's
water insoluble
ammonium salt
water soluble
c. CH3CH2NH2
H
d.
1° amine with 2 C's
water soluble
N
H
Cl–
ammonium salt
water soluble
18.19 Draw the products of each reaction.
a. [(CH3CH2)3NH] Br–
b.
(CH3CH2NH3) HSO4–
NaOH
NaOH
H
c.
(CH3CH2)3N + H2O + NaBr
N
H
Cl–
NaOH
NH
+ H2O + NaCl
CH3CH2NH2 + H2O + NaHSO4
18.20 Draw the structure of each amine from which the ammonium salt is derived.
O
HO
OH
CCH2CH3
CHCH2 N CH3
C CH2 CH N CH3
H
phenylephrine
CH3 CH3
methadone
18.21 A quaternary ammonium salt like Bitrex has four R groups bonded to N, so there is no proton
available that can be removed to form an amine.
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Amines and Neurotransmitters 18–6
18.22 The chirality center in each compound is labeled.
HO
*
HO
CH2CHNH2
*
HO
CH2CHNH2
COOH
COOH
tyrosine
* = chirality center
L-dopa
HO
HO
OH
HO
CHCH2NH2
HO
*
norepinephrine
CH2CHNH2
dopamine
H
achiral
18.23 COOH must be removed and OH must be added.
The COOH group is removed,
and the OH group is added.
CH2CH2NH2
CH2CHNH2
HO
COOH
N
H
N
H
tryptophan
serotonin
18.24 Serotonin, bufotenin, and psilocin have the same ring system with a two-carbon chain containing a
N atom bonded to it. They all contain an OH group bonded to the six-membered ring.
1o
3o
CH2CH2NH2
HO
3o
OH
CH2CH2N(CH3)2
CH2CH2N(CH3)2
HO
2o
N
H
N
H
serotonin
2o
N
H
bufotenin
2o
psilocin
18.25 To convert phenylephrine to methamphetamine requires the addition of a methyl group and
removal of two OH groups.
18.26 The atoms of 2-phenylethylamine are in bold in each compound.
O
CH3O
a.
CH3O
CH3O
(CH3CH2)2N
CH2CH2NH2
mescaline
C
N
CH3
b.
LSD
N
H
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Chapter 18–7
18.27 Classify each alcohol and amine as 1°, 2°, or 3°. OH groups not labeled are phenols.
2° alcohol
2° alcohol
OH
OH
HO
1° alcohol
CHCH2NHC(CH3)3
HO
2° amine
HOCH2
1° alcohol
albuterol
(Trade names: Ventolin, Proventil)
HOCH2
CHCH2NH(CH2)6O(CH2)4
2° amine
salmeterol
(Trade name: Serevent)
18.28 Draw the complete structure for cimetidine.
H
H H
H H
H C N
C
S
C
C
N
C
N C H
C
H
H H H N
H
N C
H
C N
H
C
H
H
Solutions to End-of-Chapter Problems
18.29
To determine whether an amine or amide is 1o, 2o, or 3o, count the number of carbons bonded to
the nitrogen atom as in Example 18.1.
3° amine
2° amide
18.30
To determine whether an amine or amide is 1o, 2o, or 3o, count the number of carbons bonded to
the nitrogen atom as in Example 18.1.
3° amide
N
3° amine
N
O
CH3
18.31
To determine whether an amine is 1o, 2o, or 3o, count the number of carbons bonded to the
nitrogen atom as in Example 18.1.
2o
a.
CH3CHCH2CH2NHCH3
3o
b.
N CH3
CH3
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Amines and Neurotransmitters 18–8
18.32 To determine whether an amine is 1o, 2o, or 3o, count the number of carbons bonded to the
nitrogen atom as in Example 18.1.
1o
3o
CH3
a.
b.
CH3CCH2NH2
N(CH3)2
CH3
18.33
Draw a structure to fit each description.
CH2CH3
a.
CH3CH2CH2CH2CH2NH2
b. CH3CH2CH2NCH2CH2CH3
c.
N CH3
d.
CH3CH2NCH2CH3
H
18.34
CH2CH3
2° amine
C6H15N
1° amine
C5H13N
+
quaternary
ammonium ion
C8H20N+
3° amine
C6H13N
Draw a structure to fit each description.
1o alcohol
1o amine
2o alcohol
3o amine
1o amine
CH3
a. HOCH2CH2CH2CH2NH2
b. CH3CHCH2NHCH3
OH
2o amine
18.35
c. HOCCH2NH2
d. CH3 N CH2CH2OH
CH3
CH3
3o alcohol
1o alcohol
Name each amine as in Example 18.2.
methyl
a.
b.
cyclohexane
cyclohexanamine
ethyl
aniline
N-ethyl-N-methylaniline
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Chapter 18–9
18.36
Name each amine as in Example 18.2.
a. CH2CH2CH2CH2CH2
N,N-dimethylpentanamine
N CH3
CH3
2 methyl groups
Cl
NH2
b.
m-chloroaniline
m-chloro
18.37
Name each amine as in Example 18.2.
H
a. CH3CH2 N CH2CH3
Answer: diethylamine
2 ethyl groups
NH2
NH2
b. CH3CH2CHCH2CH2CH2CH2CH3
octane
(8 C's)
CH3CH2CHCH2CH2CH2CH2CH3
1
octanamine
NHCH3
c.
CH3CH2CH2CHCH2CH3
hexane
(6 C's)
3 2
18.38
Answer: N-methyl-3-hexanamine
1
2
CH3CHCH2CH2CH2CH2CH3
NHCH2CH3
heptane
(7 C's)
N-methyl
CH3CH2CH2CHCH2CH3
hexanamine
CH3CHCH2CH2CH2CH2CH3
3
NHCH3
1
d.
2
Answer: 3-octanamine
NHCH2CH3
Answer: N-ethyl-2-heptanamine
N-ethyl
heptanamine
Name each amine as in Example 18.2.
a. CH3(CH2)6NH2
heptanamine
heptane
(7 C's)
b.
NHCH2CH3
cyclopentane
(5 C ring)
Answer: 1-heptanamine
Answer: N-ethylcyclopentanamine
N-ethyl
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Amines and Neurotransmitters 18–10
c.
Answer: N-ethylpyrrolidine
N CH2CH3
pyrrolidine
N-ethyl
1
CH3CHCH3
d.
N CH2CH3
3
N CH2CH3
CH3
CH3
propanamine
propane
(3 C's)
18.39
2
CH3CHCH3
Answer: N-ethyl-N-methyl-2-propanamine
N-ethyl
N-methyl
Work backwards to draw the structure corresponding to each name.
a. 1-decanamine
d. 3-aminobutanoic acid
3
CH3CH2CH2CH2CH2CH2CH2CH2CH2CH2NH2
CH3CHCH2COOH
NH2
3-amino
b. tricyclohexylamine
1
e. N,N-dipropyl-2-octanamine
CH3CH2CH2CH2CH2CH2CHCH3
N(CH2CH2CH3)2
N
N,N-dipropyl
3 cyclohexyl groups
f. N-ethylhexylamine
c. p-bromoaniline
CH3CH2NHCH2CH2CH2CH2CH2CH3
NH2
p-bromo
18.40
N-ethyl
Br
Work backwards to draw the structure corresponding to each name.
a. cyclobutylamine
d. 3-amino-2-butanone
NH2
3 O
CH3CHCCH3
b. 4-nonanamine
NH2 1
3-amino
4
CH3CH2CH2CHCH2CH2CH2CH2CH3
NH2
e. 3-methyl-1-butanamine
1
3
CH3CHCH2CH2NH2
CH3
c. N-pentylaniline
f. N-ethyl-N-propylcyclopentylamine
NHCH2CH2CH2CH2CH3
N CH2CH2CH3
N-pentyl
N-ethyl
CH2CH3
N-propyl
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Chapter 18–11
18.41
Draw the structures to illustrate the differences between N,N-dimethylaniline and 2,4diethylaninline
3° amine
1° amine
NH2
N(CH3)2
CH3CH2
N,N-dimethylaniline
18.42
CH2CH3
2,4-diethylaniline
Draw the structures to illustrate the differences between N-butylaniline and o-butylaniline.
2° amine
1° amine
NH(CH2)3CH3
NH2
CH2CH2CH2CH3
N-butylaniline
18.43
o-butylaniline
Work backwards from the name to draw each ammonium salt.
a. dipropylammonium chloride
+
[(CH3CH2CH2)2NH2] Cl–
b. butylammonium bromide
c. ethyldimethylammonium hydroxide
+
+
(CH3CH2CH2CH2NH3) Br–
ethyl
CH3CH2N(CH3)2
OH–
H
dimethyl
18.44
Work backwards from the name to draw each ammonium salt.
a. cyclohexylammonium fluoride
b. triethylammonium iodide
c. ethylmethylammonium chloride
H
CH2CH3
+
NH3 F–
CH3CH2
ethyl
NH+ I–
H
CH2CH3
18.45
+
CH3CH2NCH3 –Cl
methyl
Draw and name the four amines of molecular formula C3H9N.
CH3
N
CH3
CH3CH2CH2NH2
CH3CH2NHCH3
trimethylamine
CH3CHNH2
CH3
CH3
1-propanamine
N-methylethanamine
2-propanamine
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Amines and Neurotransmitters 18–12
18.46
Draw and name the eight constitutional isomers of molecular formula C4H11N. Identify the
chirality center present in one of the amines.
chirality center
NH2
*
CH3CH2CHCH
3
CH3CH2CH2CH2NH2
CH3CHCH2NH2
1-butanamine
CH3CCH3
CH3
NH2
CH3
2-aminobutane
2-methyl-1-propanamine
CH3CH2NHCH2CH3
CH3CHNHCH3
CH3CH2NCH3
N-methyl-2-propanamine
N,N-dimethylethanamine
2-amino-2-methylpropane
CH3
CH3CH2CH2NHCH3
diethylamine
N-methyl-1-propanamine
CH3
18.47
Pyridine is capable of hydrogen bonding with water, so it is more water soluble than benzene.
Pyridine has a higher boiling point than benzene because it contains polar C–N bonds, while
benzene is a nonpolar hydrocarbon.
18.48
CH3CH2CH2NH2 is water soluble because it is capable of hydrogen bonding with water.
CH3CH2CH2CH3 is not water soluble because it is a nonpolar hydrocarbon and cannot hydrogen
bond to water.
18.49
Determine the compound in each pair with a higher boiling point, using the rules in Example
18.3.
a.
CH3CH2CH2NH2
or
CH3(CH2)7NH2
3 C amine
b.
CH3(CH2)6OH
8 C amine
higher
boiling point
or
CH2N(CH3)2
or
3° amine
no N–H bonds
CH2CH2CH2NH2
1° amine
N–H bonds
higher
boiling point
CH3(CH2)6NH2
alcohol
higher
boiling point
18.50
c.
amine
Determine the compound in each pair with the higher boiling point using the rules in Example
18.3.
a.
(CH3CH2)2C O
or
ketone
(CH3CH2)2CHNH2
amine
higher
boiling point
Cl
c.
CH3CHCH2CHCH3
1° amine
b.
or
hydrocarbon
NH
+
NH2
NH3 Cl–
or
CH3CH2CH2CHCH3
ammonium salt
higher
boiling point
amine
higher
boiling point
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Chapter 18–13
18.51
The hydrogen bond is drawn as a dashed line.
CH2CH3
CH3CH2
H N
CH2CH3
N H
CH3CH2
18.52
The hydrogen bond is drawn as a dashed line.
H
CH3CH2
O
N H
H
CH3CH2
18.53
Primary amines can hydrogen bond to each other, whereas 3o amines cannot. Therefore, 1o
amines have higher boiling points than 3o amines of similar size. Since all amines contain
nitrogen atoms, any amine can hydrogen bond to water. Therefore, 1o and 3o amines have similar
solubility properties.
18.54
CH3(CH2)5NH3+Cl is more water soluble than CH3(CH2)5NH2 because the ammonium salt is an
ionic solid and therefore soluble in water. CH3(CH2)5NH2 contains six carbons and is therefore
not water soluble.
18.55
Draw the reaction of each amine with water by transferring a proton from H2O to the amine.
a. CH3CH2NH2 + H2O
(CH3CH2NH3)
+ OH–
+
b. (CH3CH2)2NH + H2O
(CH3CH2)2NH2
c. (CH3CH2)3N + H2O
18.56
+
(CH3CH2)3NH
+
+ OH–
+ OH–
Draw the ammonium salt that is formed when each amine is treated with HCl.
+
NH3 Cl –
a.
NH2
+ HCl
b.
CH2NHCH3
+ HCl
+
CH2NH2CH3 Cl –
c.
N(CH2CH3)2
+ HCl
+
NH(CH2CH3)2 Cl –
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Amines and Neurotransmitters 18–14
18.57
Draw the products of each reaction.
a. CH3CH2CH2N(CH3)2
+
NH2
+
H2SO4
+
Cl–
+
NH3
b. CH CH CHCH CH
3
2
2
3
+
CH3CH2CH2NH(CH3)2
HCl
CH3CH2CHCH2CH3
+
HSO4–
+
c.
+
Br–
+
HBr
N
N
H
H
+
N CH2CH3
d. CH3CH2
CH3CH2
+ NaOH
CH2CH3
18.58
CH2CH3
+ H2O
+ Na+
CH2CH3
Draw the products of each acid–base reaction.
a.
+
HCl
b. CH3CH2CHCH2CH3
+
H2SO4
CH3CH2CHCH2CH3
NHCH3
c. CH3NH2 +
d.
Cl–
+
+
N
H
N
18.59
N
+
HSO4–
NH2CH3
+
+
CH3NH3
CH3COOH
+
CH3(CH2)5NH3 + NaOH
CH3(CH2)5NH2
+
CH3COO–
+ H2O
+ Na+
Draw the products of each reaction.
+
a.
HCl
N
H
N
CH2CH2CH3
H
HO
b.
+
HO
HCl
O
O
N
HO
H
CH3
N
HO
Cl–
CH2CH2CH3
Cl–
H
CH3
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Chapter 18–15
18.60
Draw the products of each reaction.
a.
CH2CHNH2
+
CH2CHNH3 HSO4–
+ H2SO4
CH3
CH3
HO
b.
18.61
HO
HO
CH2CH2NH2 + H2SO4
+
CH2CH2NH3 HSO4–
HO
The heterocycle in both coniine and morphine is piperidine (labeled in bold).
HO
O
N
H
N
CH2CH2CH3
coniine
18.62
CH3
HO
morphine
The pyrrolidine N is trigonal pyramidal because it is surrounded by four groups, three of which
are bonds and one of which is a lone pair of electrons. The pyridine N has only three groups
around it, two of which are bonds and one of which is a lone pair. The pyridine N doesn’t have
enough groups around it to be trigonal pyramidal.
N
trigonal planar
N
CH3
trigonal pyramidal
18.63
Caffeine is a mild stimulant, imparting a feeling of alertness after consumption. It also increases
heart rate, dilates airways, and stimulates the secretion of stomach acid. These effects are
observed because caffeine increases glucose production, making an individual feel energetic.
18.64
Caffeine intake should be limited in pregnant and nursing mothers because excessive
consumption increases the risk of miscarriage and caffeine can pass into breast milk, possibly
affecting the health of a newborn baby.
18.65
An alkaloid solution is slightly basic since its amine pulls off a proton from water, forming OH–
and an ammonium ion.
18.66
a. Morphine is found in poppies and is used as a pain reliever for people suffering from severe
chronic pain.
b. Quinine is found in the bark of the cinchona tree and is used to treat malaria.
c. Atropine is found in the nightshade plant and is used to increase heart rate.
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Amines and Neurotransmitters 18–16
18.67
Dopamine affects brain processes that control movement, emotions, and pleasure. Normal
dopamine levels give an individual a pleasurable, satisfied feeling. Increased levels result in an
intense “high.” Drugs such as heroin, cocaine, and alcohol increase dopamine levels. When there
is too little dopamine in the brain, an individual loses control of fine motor skills and Parkinson’s
disease results.
18.68
Patients with Parkinson’s disease cannot be treated by giving them dopamine, even though the
disease results from low dopamine levels, because dopamine does not cross the blood–brain
barrier.
18.69
Serotonin plays an important role in mood, sleep, perception, and temperature regulation. We get
sleepy after eating a turkey dinner on Thanksgiving because the unusually high level of
tryptophan in turkey is converted to serotonin. A deficiency of serotonin causes depression.
18.70
Two examples of SSRIs are fluoxetine (Prozac) and sertraline (Zoloft). They combat depression
by inhibiting the reuptake of serotonin by the presynaptic neuron.
18.71
Dopamine [part (a)] and norepinephrine [part (b)] are derived from tyrosine, serotonin [part (c)] is
derived from tryptophan, and histamine [part (d)] is derived from histidine.
18.72
A neurotransmitter is a chemical messenger that transmits nerve impulses from one nerve cell
(neuron) to another cell. A hormone is a compound produced by an endocrine gland, which then
travels through the bloodstream to a target tissue or organ.
18.73
The atoms of 2-phenylethylamine are labeled in bold in the compounds below.
CH3
a.
CH2CH2CH2NH2
HN
c.
b.
C CH2N(CH3)2
CH2
CH3
not a derivative of
2-phenylethylamine
18.74
The atoms of 2-phenylethylamine are labeled in bold in the compounds below.
CH3 CH3
a.
C
C CH3
b.
CH2NH
c.
CH2CH2 N
CH3 NHCH3
not a derivative of
2-phenylethylamine
18.75
The atoms of 2-phenylethylamine are labeled in bold.
CH3
CH2CNH2
CH3
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manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part.
Chapter 18–17
18.76
The atoms of 2-phenylethylamine are labeled in bold.
OH
HO
CHCH2NHC(CH3)3
HOCH2
18.77
Chlorpheniramine is an example of an antihistamine. Antihistamines bind to the H1 histamine
receptor, but they evoke a different response than histamine. An antihistamine like
chlorpheniramine or diphenhydramine, for example, inhibits vasodilation, so it is used to treat the
symptoms of the common cold and environmental allergies.
18.78
Cimetidine is an anti-ulcer drug. It binds to the H2 histamine, thus reducing acid secretions in the
stomach.
18.79
Answer each question about benzphetamine.
3o amine
a. and b.
CH3
CH2CHNCH2
CH3
chirality center
c.
CH3 H
H
CH3
C
C
NCH2
H
H
CH3
CH3
C
C
CH3 H
H
CH2N
enantiomers
CH3
CH2CHNH2
d.
CH2
1° amine
constitutional isomer
CH2CH2N
e.
CH3
CH3
CH2
3° amine
constitutional isomer
CH3
f.
CH2CHNHCH2
+
Cl–
benzphetamine hydrochloride
CH3
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manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part.
Amines and Neurotransmitters 18–18
+ CH3COOH
CH2CHNCH2
+ CH3COO–
CH2CHNHCH2
CH3
CH3
18.80
+
CH3
CH3
g.
Answer each question about phentermine.
CH3
a.
1o amine
CH2CNH2
CH3
trigonal planar
tetrahedral
CH3
b.
trigonal pyramidal
CH2CNH2
CH3
tetrahedral
c.
CH2CHCH2NH2
CH3
d.
CH2CHNHCH3
CH3
CH3
+
CH2CNH3 Br–
e.
CH3
f.
CH2CNH2
CH3
O
CH3
+
HO C
+
–
OC
CH3
CH3
18.81
O
+
CH2CNH3
Answer the questions about Ritalin.
aromatic ring
a., b., and c.
chirality center
2o amine
HN
CH
COOCH3
e.
H
H N
CH
+
Cl–
COOCH3
ester
d. 2-phenylethylamine in bold
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manner. This document may not be copied, scanned, duplicated, forwarded, distributed, or posted on a website, in whole or part.
Chapter 18–19
18.82
Answer the questions about seldane.
2° alcohol
a., b., c., d., and e.
(CH3)3C
3° amine
3° alcohol
OH
OH
CHCH2CH2CH2 N
C
aromatic ring
chirality center
quaternary carbon
aromatic ring
Cl–
OH
f.
18.83
(CH3)3C
OH
+
CHCH2CH2CH2 N
C
Work backwards to draw the structure of the amine and carboxylic acid that are used to form
Chlortrimeton, an ammonium salt.
H
Cl
CHCH2CH2N(CH3)2
N
H
H
Cl
C C
HOOC
COOH
CHCH2CH2N(CH3)2
N
+
H
H
C C
HOOC
chlorpheniramine maleate
Chlortrimeton
18.84
Draw the structure of the dextromethorphan hydrobromide.
CH3O
Br–
+
NH
CH3
18.85
A vasodilator dilates blood vessels and a bronchodilator dilates airways in the lungs. Histamine is
a vasodilator and albuterol is a bronchodilator.
18.86
Antihistamines that cause drowsiness are able to cross the blood–brain barrier and bind to H1
receptors in the central nervous system. Antihistamines that do not cause drowsiness also bind to
H1 receptors, but they are unable to cross the blood–brain barrier and bind to the H1 receptors in
the central nervous system.
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COO–
Amines and Neurotransmitters 18–20
18.87
Albuterol will exist in the ionic form in the stomach (lower pH) and in the neutral form in the
intestines.
OH
HO
HOCH2
OH
+
CHCH2NH2CH(CH3)3
HO
ionic form
CHCH2NHC(CH3)3
HOCH2
neutral form
albuterol
18.88
Eating a poppy seed bagel can produce a positive test in a drug screening because poppy seeds
contain morphine.
18.89
Heroin has two esters, which can be made from the two OH groups in morphine. Add acetic acid
(CH3COOH) and H2SO4 to make the two esters in heroin.
CH3
HO
Both OH groups are
converted to esters.
CH3COOH
H2SO4
O
O
O
CH3
CH3
C
N
CH3
O
heroin
morphine
18.90
O
O
N
HO
C
The compound that might cause the odor that allows for heroin detection is acetic acid, the main
ingredient in vinegar.
CH3
C
HO
O
O
O
O
+ 2 H2O
O
CH3
C
N
CH3
O
2
CH3
C
+
O
OH
acetic acid
(vinegar)
N
HO
CH3
heroin
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