1. Introductory Chemistry, 3rd Edition Nivaldo Tro
Chapter 18
Organic
Chemistry
Roy Kennedy
Massachusetts Bay Community College
Wellesley Hills, MA
2009, Prentice Hall

2. What Is Organic Chemistry?
Organic chemistry is a branch of chemistry that focuses on compounds that contain carbon.
Except CO, CO2, carbonates, and carbides.
Even though organic compounds only contain a few elements, the unique ways carbon atoms can attach together to form molecules leads to millions of different organic compounds.
Tro's Introductory Chemistry, Chapter 18

3. Tro's Introductory Chemistry, Chapter 18
The Chemistry of Life
Life as we know it is because of organic chemistry.
Organic molecules can be very large and complex.
It is this complexity of large organic molecules that allows the complex functions of the cells to occur.
Tro's Introductory Chemistry, Chapter 18

4. The Origins of Organic Chemistry Vitalism
The classification of matter really started at the end of the 1700s.
When chemists tried to classify compounds, they found vast differences between the compounds found in living and nonliving things.
They, therefore, believed that compounds found in living systems possessed a special “vital force” that made life possible.
Tro's Introductory Chemistry, Chapter 18

5. Classifying Pure Substances, the Old Way
Some
Yes No
Yes No
Tro's Introductory Chemistry, Chapter 18

6. Differences Between Organic and Inorganic Compounds
Organic compounds are easily decomposed into simpler substances by heating, but inorganic substances are not.
Inorganic were readily synthesized in the lab, but nobody was able to synthesize organic compounds in the lab.
Tro's Introductory Chemistry, Chapter 18

7. Tro's Introductory Chemistry, Chapter 18
The Death of Vitalism
If organic compounds contained a vital force but inorganic compounds did not, then it should be impossible to make an organic compound from an inorganic one.
Wöhler’s synthesis of the organic compound urea from the inorganic compound ammonium cyanate proved you could make organic compounds from inorganic ones—therefore, there cannot be a vital force.
Tro's Introductory Chemistry, Chapter 18

8. Classifying Pure Substances, the Modern Way
Some
Yes No
Yes No
Tro's Introductory Chemistry, Chapter 18

9. What’s Special About Organic Compounds?
Organic compounds tend to be molecular.
Mainly composed of just six nonmetallic elements.
C, H, O, N, S, and P.
Compounds found in all three states.
Solids, liquids, and gases.
Solids tend to have low melting points.
Solubility in water varies depending on which of the other elements are attached to C and how many there are.
CH3OH is miscible with water; C10H21OH is insoluble.
Tro's Introductory Chemistry, Chapter 18

10. What’s So Special About Carbon?
Carbon atoms can do some unique things that other atoms cannot.
Carbon can bond to as many as four other atoms.
Bonds to carbon are very strong and nonreactive.
Carbon atoms can attach together in long chains.
Carbon atoms can attach together to form rings.
Carbon atoms can form single, double, or triple bonds.
Tro's Introductory Chemistry, Chapter 18

11. Bond Energies and Reactivities
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12. Tro's Introductory Chemistry, Chapter 18
Carbon
Carbon forms four bonds.
When C has four single bonds, the shape is tetrahedral.
When C has one triple + one single or two double bonds, the shape is linear.
When C has two single + one double bond, the shape is trigonal planar.
Tro's Introductory Chemistry, Chapter 18

13. Practice—Predict the Shape Around Each C Atom.
HCN
CH3CH2CH3
H2CNH
HCO2H
C2H3Cl
C3H4
Tro's Introductory Chemistry, Chapter 18 13

14. Practice—Predict the Shape Around Each C Atom, Continued.
HCN
CH3CH2CH3
H2CNH
HCO2H
C2H3Cl
C3H4
Linear
Trigonal planar
All tetrahedral
Both trigonal planar
Center = linear
Outer = trigonal planar
Both trigonal planar
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15. Tro's Introductory Chemistry, Chapter 18
Hydrocarbons
Hydrocarbons contain only C and H.
Two classes of hydrocarbons: saturated or unsaturated.
Insoluble in water.
No polar bonds to attract water molecules.
May be chains or rings.
Ring molecules have less H than chain so that the ends can join.
Chains may be straight or branched.
Rings may be aliphatic or aromatic.
Tro's Introductory Chemistry, Chapter 18

16. Uses of Hydrocarbons Number of C atoms State Major uses 1–4 gas
heating and cooking fuel
5–7
liquids,
(low boiling)
solvents, gasoline
6–18
liquids
gasoline
12–24
jet fuel; camp stove fuel
18–50
(high boiling)
diesel fuel, lubricants, heating oil
50+
solids
petroleum jelly, paraffin wax
1–4
Gas
heating and cooking fuel
5–7
Liquids
(low boiling)
solvents, gasoline
6–18
Liquids
gasoline
12–24
Liquids
jet fuel, camp stove fuel
18–50
Liquids
(high boiling)
diesel fuel, lubricants, heating oil
50+
Solids
petroleum jelly, paraffin wax

17. Saturated Hydrocarbons
A saturated hydrocarbon has all C—C single bonds.
It is saturated with hydrogens.
Saturated hydrocarbons are called alkanes.
Chain alkanes have the general formula CnH2n+2.
Chains may be straight or branched.
“Normal” isomer is the straight chain.
Ring alkanes have two fewer Hs per ring than the corresponding chain isomer.
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18. Unsaturated Hydrocarbons
Unsaturated hydrocarbons have one or more C=C double bonds, CC triple bonds, or aromatic rings.
Unsaturated hydrocarbons that contain C=C are called alkenes.
The general formula of a monounsaturated chain alkene is CnH2n.
Remove two more Hs for each additional unsaturation.
Unsaturated hydrocarbons that contain CC are called alkynes.
The general formula of a monounsaturated chain alkyne is CnH2n-2.
Remove four more Hs for each additional unsaturation.
Tro's Introductory Chemistry, Chapter 18

19. Some Unsaturated Hydrocarbons
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20. Aromatic Hydrocarbons
Aromatic hydrocarbons contain a ring structure that seems to have C=C, but doesn’t behave that way.
The most prevalent example is benzene.
C6H6.
Other compounds have the benzene ring with other groups substituted for some of the Hs.
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21. Tro's Introductory Chemistry, Chapter 18
Hydrocarbons
Tro's Introductory Chemistry, Chapter 18

22. Types of Hydrocarbons
Alkynes
alkanes
alkenes 22

23. Tro's Introductory Chemistry, Chapter 18
Practice—Assuming Only Chains with a Maximum of One Unsaturation, Decide if Each of the Following Molecular Formulas Represents an Alkane, Alkene, or Alkyne.
C14H28
C25H52
C12H10
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24. Tro's Introductory Chemistry, Chapter 18
Practice—Assuming Only Chains with a Maximum of One Unsaturation, Decide if Each of the Following Molecular Formulas Represents an Alkane, Alkene, or Alkyne, Continued.
C14H28 Alkene.
C25H52 Alkane.
C12H10 Alkyne.
Tro's Introductory Chemistry, Chapter 18

25. Formulas
Molecular formulas just tell you what kinds of atoms are in the molecule, but they don’t tell you how they are attached.
Structural formulas show you the attachment pattern in the molecule.
Models not only show you the attachment pattern, but give you an idea about the shape of the molecule.

26. Condensed Structural Formulas
Attached atoms listed in order.
Central atom with attached atoms.
Follow normal bonding patterns.
Use to determine position of multiple bonds.
() used to indicate more than one identical group attached to same previous central atom.
Unless () group listed first in which case attached to next central atom.
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27. Carbon Skeleton Formulas
A.k.a. line-angle formulas.
Used very often with ring structures.
Each angle, and its beginning and end represent a C atom.
H omitted on C.
Included on functional groups.
Multiple bonds indicated.
Double line is double bond; triple line is triple bond.
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28. Tro's Introductory Chemistry, Chapter 1828

29. Tro's Introductory Chemistry, Chapter 18
Example 18.2—Write the Structural and Condensed Formula for the n-Alkane C8H18.
Connect the C atoms in a row.
Carbon skeleton.
Add H to complete four bonds on each C.
Middle C gets 2 Hs.
End C gets 3 Hs.
The condensed formula has the H attached to each C written directly after it.
CH3CH2CH2CH2CH2CH2CH2CH3
Tro's Introductory Chemistry, Chapter 18

30. Practice—Write a Complete Structural Formula for C7H16.
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31. Practice—Write a Complete Structural Formula for C7H16, Continued.
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32. Tro's Introductory Chemistry, Chapter 18
Alkanes
Also know as paraffins.
Aliphatic, saturated.
General formula CnH2n+2 for chains.
Very unreactive.
CH3 groups at ends of chains; CH2 groups in the middle.
Chains may be straight or branched.
n-Alkane = straight chain.
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33. Tro's Introductory Chemistry, Chapter 18
Structural Isomers
Isomers are molecules with the same molecular formula, but different arrangements of the atoms.
Different chemical and physical properties.
Structural isomers are isomers in which the atoms are attached differently.
Different bonding pattern.
Structural isomers have different physical properties.
Structural isomers may give different products in a reaction, though they undergo the same types of reactions.
Tro's Introductory Chemistry, Chapter 18

34. Structural Isomers of C4H10
Butane, BP = 0 °C
Isobutane, BP = -12 °C
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35. Possible Structural Isomers
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36. Tro's Introductory Chemistry, Chapter 18
Example—Write the Structural Formula and Carbon Skeleton Formula for C6H14.
Start by connecting the carbons in a line.
Determine the C skeleton of the other isomers.
Tro's Introductory Chemistry, Chapter 18 36

37. Example—Write the Structural Formula and Carbon Skeleton Formula for C6H14, Continued.
Fill in the Hs to give each C four bonds.

38. Example—Write the Structural Formula and Carbon Skeleton Formula for C6H14, Continued.
Convert each to a carbon skeleton formula— each bend and the ends represent C atoms.

39. Example—Draw All Nine Structural Isomers of Heptane.
The prefix hept- means 7, so the molecular formula is C7H16.
Start by drawing the carbon skeleton of the straight chain isomer:
Tro's Introductory Chemistry, Chapter 18

40. Example—Draw All Nine Structural Isomers of Heptane, Continued.
Take one C off the right end of the straight chain isomer and attach it to the second C in from the left end.
Then keep moving it down the chain to the half-way point.
Tro's Introductory Chemistry, Chapter 18

41. Example—Draw All Nine Structural Isomers of Heptane, Continued.
Take one C off the right end of each one-branch chain isomer and attach it to the second C in from the left end.
Then keep moving it down the chain.
Always keep checking to ensure you do not duplicate.
already have
Tro's Introductory Chemistry, Chapter 18

42. Example—Draw All Nine Structural Isomers of Heptane, Continued.
Take one C chain off the right end of 2,2-branch isomer and attach it to the third C in from the left end.
Then keep moving it down the chain.
Repeat with other two branch isomers if necessary.
Tro's Introductory Chemistry, Chapter 18

43. Example—Draw All Nine Structural Isomers of Heptane, Continued.
Take two C chains off the right end of a straight chain isomer and attach it to the third C in from the left end.
Then keep moving it down the chain half way.
Tro's Introductory Chemistry, Chapter 18

44. Example—Draw All Nine Structural Isomers of Heptane, Continued.
Continue the process until you’ve drawn all the isomers.
Tro's Introductory Chemistry, Chapter 18

45. Example—Draw All Nine Structural Isomers of Heptane, Continued.
Fill in the hydrogens so each C has four bonds.

46. Practice—Draw the Three Structural Isomers of Pentane.
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47. Practice—Draw the Three Structural Isomers of Pentane, Continued.
Tro's Introductory Chemistry, Chapter 18

48. Alkanes—Physical Properties
Nonpolar molecules, intermolecular attractions due to induced dipoles.
Both boiling points and melting points generally increase as the size of the molecule increases.
Insoluble in water, commonly used as nonpolar solvents.
Less dense than water, density increases with size.
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49. Physical Properties of n–Alkanes
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50. Tro's Introductory Chemistry, Chapter 18

51. Tro's Introductory Chemistry, Chapter 18
Alkane Boiling Points
Branched chains have lower boiling points than straight chains.
Cycloalkanes have higher boiling points than straight chains.
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52. Select the Molecule in Each Pair with the Higher Boiling Point.

53. Select the Molecule in Each Pair with the Higher Boiling Point, Continued.

54. Tro's Introductory Chemistry, Chapter 18
Naming
Each name consists of three parts:
Prefix.
Indicates position, number, and type of branches.
Indicates position, number, and type of each functional group.
Parent.
Indicates the length of the longest carbon chain or ring.
Suffix.
Indicates the type of hydrocarbon.
-ane, -ene, -yne
Certain functional groups.
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55. Tro's Introductory Chemistry, Chapter 18
Naming Alkanes
Find the longest, continuous carbon chain.
Number the chain from the end closest to a branch.
If first branches equal distance, use the next in.
Name branches as alkyl groups.
Locate each branch by preceding its name with the carbon number on the chain.
List branches alphabetically.
Do not count n-, sec-, t-, but count iso.
Use prefix if more than one of the same group is present.
di-, tri-, tetra-, penta-, hexa-.
Do not count in alphabetizing.
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56. Branches—Alkyl Groups3 - , M E T Y L 2 P R O ( ) I S
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57. Tro's Introductory Chemistry, Chapter 18
More Alkyl Groups C H 3 ( ) 2 - , I S O B U T Y L s e c n
tert-
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58. Examples of Naming Alkanes
H H H H H
H C C C C C H
H CH3 H H H
2-methylpentane
H CH3 H H H H
H C C C C C C H
H CH3 CH H H H
CH3 CH3
3-isopropyl-2,2-dimethylhexane
Tro's Introductory Chemistry, Chapter 18

59. Example 18.6—Name the Alkane.
1. Find the longest, continuous C chain and use it to determine the base name.
Since the longest chain has 5 Cs,
the base name is pentane.
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60. Example 18.6—Name the Alkane, Continued.
2. Identify the substituent branches.
There are two substituents.
Both are one C chains called methyl.
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61. Example 18.6—Name the Alkane, Continued.
3. Number the chain from the end closest to a substituent branch.
If first substituents equidistant from end, go to next substituent in.
Then assign numbers to each substituent based
on the number of the main chain C to which its
attached.
Both substituents are equidistant from the end.
Tro's Introductory Chemistry, Chapter 18

62. Example 18.6—Name the Alkane, Continued.
4. Write the name in the following order:
Substituent number of first alphabetical substituent followed by dash.
Substituent name of first alphabetical substituent followed by dash.
If it’s the last substituent listed, no dash.
Use prefixes to indicate multiple identical substituents.
Repeat for other substituents alphabetically.
Name of main chain.
2,4 –
dimethyl
pentane
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63. Practice—Name the Following:
Tro's Introductory Chemistry, Chapter 18

64. Practice—Name the Following, Continued:
3-ethyl-2-methylpentane
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65. Practice—Draw and Name All Nine Structural Isomers of Heptane.
Tro's Introductory Chemistry, Chapter 18 65

66. Tro's Introductory Chemistry, Chapter 18
Practice—Draw and Name All Nine Structural Isomers of Heptane, Continued.
The prefix hept- means 7, so the molecular formula is C7H16.
Start by drawing the carbon skeleton of the straight chain isomer:
Tro's Introductory Chemistry, Chapter 18 66

67. Tro's Introductory Chemistry, Chapter 18
Practice—Draw and Name All Nine Structural Isomers of Heptane, Continued.
Take one C off the right end of the straight chain isomer and attach it to the second C in from the left end.
Then keep moving it down the chain to the half-way point.
Tro's Introductory Chemistry, Chapter 18 67

68. Tro's Introductory Chemistry, Chapter 18
Practice—Draw and Name All Nine Structural Isomers of Heptane, Continued.
Take one C off the right end of each one-branch chain isomer and attach it to the second C in from the left end.
Then keep moving it down the chain.
Always keep checking to ensure you do not duplicate.
already have
Tro's Introductory Chemistry, Chapter 18 68

69. Tro's Introductory Chemistry, Chapter 18
Practice—Draw and Name All Nine Structural Isomers of Heptane, Continued.
Take one C chain off the right end of 2,2-branch isomer and attach it to the third C in from the left end.
Then keep moving it down the chain.
Repeat with other two branch isomers if necessary.
Tro's Introductory Chemistry, Chapter 18 69

70. Tro's Introductory Chemistry, Chapter 18
Practice—Draw and Name All Nine Structural Isomers of Heptane, Continued.
Take two C chain off the right end of straight chain isomer and attach it to the third C in from the left end.
Then keep moving it down the chain to half way.
Tro's Introductory Chemistry, Chapter 18 70

71. Tro's Introductory Chemistry, Chapter 18
Practice—Draw and Name All Nine Structural Isomers of Heptane, Continued.
Continue the process until you’ve drawn all the isomers.
Tro's Introductory Chemistry, Chapter 18 71

72. Tro's Introductory Chemistry, Chapter 18
Practice—Draw and Name All Nine Structural Isomers of Heptane, Continued.
Find the base name of each main chain.
Heptane
and
Hexanes
Pentanes
Butane
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73. Tro's Introductory Chemistry, Chapter 18
Practice—Draw and Name All Nine Structural Isomers of Heptane, Continued.
Number the main chain from end closest to substituent.
Heptane
and
Hexanes
Pentanes
Butane
Tro's Introductory Chemistry, Chapter 18

74. Practice—Draw and Name All Nine Structural Isomers of Heptane, Continued.
Name and number alkyl groups.
Heptane
2-methylhexane
3-methylhexane
3-ethylpentane
2,2-dimethylpentane
2,4-dimethylpentane
2,2,3-trimethylbutane
2,3-dimethylpentane
3,3-dimethylpentane

75. Practice—Draw and Name All Nine Structural Isomers of Heptane, Continued.
Fill in the hydrogens so each C has four bonds.

76. Drawing Structural Formulas
4-ethyl-2-methylhexane
Draw and number the base chain carbon skeleton.
Add the carbon skeletons of each substituent on the appropriate main chain C.
Add in required Hs.
Tro's Introductory Chemistry, Chapter 18

77. Practice—Draw the Structural Formula of 4-isopropyl-2-methylheptane.
Tro's Introductory Chemistry, Chapter 18

78. Tro's Introductory Chemistry, Chapter 18
Practice—Draw the Structural Formula of 4-isopropyl-2-methylheptane, Continued.
Tro's Introductory Chemistry, Chapter 18

79. Alkenes Also known as olefins. Aliphatic, unsaturated.
C=C double bonds.
Formula for one double bond = CnH2n.
Subtract two Hs from alkane for each double bond.
Trigonal shape around C.
Flat.
Much more reactive than alkanes.
Polyunsaturated = many double bonds. 79

80. n–1–Alkenes

81. Tro's Introductory Chemistry, Chapter 18
Alkenes
Ethene = ethylene
Propene
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82. Physical Properties of Alkenes
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83. Tro's Introductory Chemistry, Chapter 18
Alkynes
Also known as acetylenes.
Aliphatic, unsaturated.
CºC triple bond.
Formula for one triple bond = CnH2n-2.
Subtract four Hs from alkane for each triple bond.
Linear shape.
More reactive than alkenes.
Tro's Introductory Chemistry, Chapter 18 83

84. Tro's Introductory Chemistry, Chapter 18
n–1–Alkynes
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85. Tro's Introductory Chemistry, Chapter 18
Alkynes
Ethyne = acetylene
Propyne
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86. Physical Properties of Alkynes
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87. Naming Alkenes and Alkynes
Find longest chain containing multiple bond.
Alkene takes precedence over alkyne.
Change suffix on main name from -ane to -ene for base name of alkene, or to –yne for the base name of the alkyne.
Number chain from end closest to multiple bond.
Number in front of main name indicates first carbon of multiple bond.
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88. Examples of Naming Alkenes
H H H
H C C C C C H
H CH3 H H H
2-methyl-1-pentene
H CH H H
H C C C C C C H
H CH3 CH H H H
CH3 CH3
3-isopropyl-2,2-dimethyl-3-hexene
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89. Examples of Naming Alkynes
H H H
H C C C C C H
CH3 H H
3-methyl-1-pentyne
H CH3 H H
H C C C C C C H
H CH3 CH H
CH3 CH3
4-isopropyl-5,5-dimethyl-2-hexyne
Tro's Introductory Chemistry, Chapter 18

90. Name the Alkene
1. Find the longest, continuous C chain that contains the double bond and use it to determine the base name.
Since the longest chain with the double bond has six Cs,
the base name is hexene.
Tro's Introductory Chemistry, Chapter 18

91. Name the Alkene, Continued
2. Identify the substituent branches.
There are two substituents.
One is a one-C chain, called methyl
and the other one is a two-C chain, called ethyl.
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92. Name the Alkene, Continued
3. Number the chain from the end closest to the double bond.
Then assign numbers to each substituent based
on the number of the main chain C to which
its attached. 4 3 1 2 3 4 5 6
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93. Name the Alkene, Continued
4. Write the name in the following order:
Substituent number of first alphabetical substituent.
Substituent name of first alphabetical substituent.
Use prefixes to indicate multiple identical substituents.
Repeat for other substituents.
Number of first C in double bond; name of main chain. 4 3
3–ethyl–
4–methyl–
2–hexene 1 2 3 4 5 6
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94. Practice—Name the Following:
Tro's Introductory Chemistry, Chapter 18

95. Practice—Name the Following, Continued:3 4 5 6 2 1
3,4-dimethyl-3-hexene
Tro's Introductory Chemistry, Chapter 18

96. Name the Alkyne
1. Find the longest, continuous C chain that contains the triple bond and use it to determine the base name.
Since the longest chain with the triple bond has seven Cs,
the base name is heptyne.
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97. Name the Alkyne, Continued
2. Identify the substituent branches.
There are 2 substituents.
One is a one-C chain, called methyl and
the other one is called isopropyl.
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98. Name the Alkyne, Continued
3. Number the chain from the end closest to the triple bond.
Then assign numbers to each substituent based
on the number of the main chain C to which
its attached. 1 2 3 4 5 6 7 4 6
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99. Name the Alkyne, Continued
4. Write the name in the following order:
Substituent number of first alphabetical substituent.
Substituent name of first alphabetical substituent.
Use prefixes to indicate multiple identical substituents.
Repeat for other substituents.
Number of first C in double bond; name of main chain. 1 2 3 4 5 6 7 4 6
4–isopropyl–
6–methyl–
2–heptyne
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100. Practice—Name the Following:
Tro's Introductory Chemistry, Chapter 18

101. Practice—Name the Following, Continued:3 2 1 4 5
3,3-dimethyl-1-pentyne
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102. Reactions of Hydrocarbons
All hydrocarbons undergo combustion.
Combustion is always exothermic.
About 90% of U.S. energy generated by combustion.
2 CH3CH2CH2CH3(g) + 13 O2(g) → 8 CO2(g) + 10 H2O(g)
CH3CH=CHCH3(g) + 6 O2(g) → 4 CO2(g) + 4 H2O(g)
2 CH3CCCH3(g) + 11 O2(g) → 8 CO2(g) + 6 H2O(g)
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103. Chemical Energy Burning hydrocarbons releases heat and light energy.
Combustion.
Alkane + oxygen ® carbon dioxide + water.
Larger alkane, more heat released.

104. Other Alkane Reactions
Substitution.
Replace H with a halogen atom.
Cl or Br.
Initiated by addition of energy in the form of heat or ultraviolet light.
To start breaking bonds.
Generally get multiple products with multiple substitutions.
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105. Predict the Products and Balance the Equations.
CH3CH3 + Br2 ® hn
+ O2 ®
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105

106. Predict the Products and Balance the Equations, Continued.
CH3CH3 + Br2 ® CH3CH2Br + HBr hn
16 CO H2O
+ 25 O2 ® 2
Tro's Introductory Chemistry, Chapter 18
106

107. Other Alkene and Alkyne Reactions
Addition reactions.
Adding a molecule across the multiple bond.
Hydrogenation = adding H2.
Converts unsaturated molecule to saturated.
Alkene or alkyne + H2 → alkane.
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108. Reactions of Alkenes Combustion Addition Reactions Hydrogenation
Hydration
Hydrohalogenation

109. Addition Reactions

110. Practice—Predict the Products.

111. Practice—Predict the Products, Continued.

112. Tro's Introductory Chemistry, Chapter 18
Aromatics
Benzene
Resonance hybrid.
Does not react like alkenes.
Reactions are generally substitutions for H. 
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113. Tro's Introductory Chemistry, Chapter 18
Line-Angle Formulas
Each angle, and beginning and end, represent a C atom.
H omitted on C.
Included on functional groups.
Multiple bonds indicated.
Double line is double bond; triple line is triple bond.
Heteroatoms written with required hydrogens.
CH(CH3)3 =
CH2CHCH3 =
CH3CH(OH)CH3 =
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114. Tro's Introductory Chemistry, Chapter 18
Resonance Hybrid
The true structure of benzene is a resonance hybrid of two structures.
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115. Naming Monosubstituted Benzene Derivatives
(Name of substituent) benzene.
Halogen substituent = change ending to “o.”
fluorobenzene
propylbenzene
Or name of a common derivative.

116. Naming Benzene as a Substituent
When the benzene ring is not the base name, it is called a phenyl group.
4-phenyl-1-hexene
Tro's Introductory Chemistry, Chapter 18

117. Naming Disubstituted Benzene Derivatives
Number the ring starting at attachment for first substituent, then move toward second.
Order substituents alphabetically.
Use “di-” if both substituents are the same. 1 2 3
1-bromo-3-fluorobenzene 1 2
1,2-dimethylbenzene
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118. Naming Disubstituted Benzene Derivatives, Continued
Alternatively, use relative position prefixes:
ortho- = 1,2; meta- = 1,3; para- = 1,4.
2-chlorotoluene
ortho-chlorotoluene
o-chlorotoluene
3-chlorotoluene
meta-chlorotoluene
m-chlorotoluene
4-chlorotoluene
para-chlorotoluene
p-chlorotoluene
Tro's Introductory Chemistry, Chapter 18

119. Practice—Name the Following:
Tro's Introductory Chemistry, Chapter 18

120. Practice—Name the Following, Continued:
1-chloro-4-fluorobenzene
1,3-dibromobenzene
or meta-dibromobenzene
or m-dibromobenzene
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121. Tro's Introductory Chemistry, Chapter 18
Functional Groups
Other organic compounds are hydrocarbons in which functional groups have been substituted for hydrogens.
A functional group is a group of atoms that show a characteristic influence on the properties of the molecule.
Generally, the reactions that a compound will perform are determined by what functional groups it has.
Since the kind of hydrocarbon chain is irrelevant to the reactions, it may be indicated by the general symbol R.
CH3—OH
R group
Functional group
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122. Functional Groups, Continued
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123. Tro's Introductory Chemistry, Chapter 18
Alcohols
R—OH.
Ethanol = CH3CH2OH.
Grain alcohol = fermentation of sugars.
Alcoholic beverages.
Proof number = 2x percentage of alcohol.
Gasohol.
Isopropyl alcohol = (CH3)2CHOH.
2-propanol.
Rubbing alcohol.
Poisonous.
Methanol = CH3OH.
Wood alcohol = thermolysis of wood.
Paint solvent.
Tro's Introductory Chemistry, Chapter 18

124. Naming Alcohols Find the main chain that contains OH.
Unless C=O present.
Number main chain from end closest to OH.
Give base name -ol ending and place number of C on chain where OH attached in front.
Name as hydroxy group if other higher precedence group present. 1 2 3 4 5 6
4-ethyl-4-methyl-3-hex-5-enol

125. Practice—Name the Following:
Tro's Introductory Chemistry, Chapter 18
125

126. Practice—Name the Following, Continued:1 3 6 5 4 2
3-isopropyl-2-methyl-2-hexanol
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126

127. Tro's Introductory Chemistry, Chapter 18
Practice—Draw a Structural Formula for 3-ethyl-2,4-dimethyl-2-pent-4-enol.
Tro's Introductory Chemistry, Chapter 18
127

128. Tro's Introductory Chemistry, Chapter 18
Practice—Draw a Structural Formula for 3-ethyl-2,4-dimethyl-2-pent-4-enol, Continued.
Tro's Introductory Chemistry, Chapter 18
128

129. Tro's Introductory Chemistry, Chapter 18
Ethers
R–O–R.
Ether = diethyl ether = CH3CH2OCH2CH3.
Anesthetic.
To name ethers, name each alkyl group attached to the O, then add the word ether to the end.
Diethyl ether
Tro's Introductory Chemistry, Chapter 18

130. Practice—Name the Following:
Tro's Introductory Chemistry, Chapter 18
130

131. Practice—Name the Following, Continued:
Isopropyl propyl ether
Tro's Introductory Chemistry, Chapter 18
131

132. Tro's Introductory Chemistry, Chapter 18
Aldehydes and Ketones
Contain the carbonyl group.
Aldehydes = at least 1 side H.
Ketones = both sides R groups.
Many aldehydes and ketones have pleasant tastes and aromas.
Some are pheromones.
Formaldehyde = H2C=O.
Pungent gas.
Formalin = a preservative.
Wood smoke, carcinogenic.
Acetone = CH3C(=O)CH3.
Nail-polish remover.
Formaldehyde
Acetone
Tro's Introductory Chemistry, Chapter 18

133. Aldehyde Odors and Flavors
Butanal = butter.
Vanillin = vanilla.
Benzaldehyde = almonds.
Cinnamaldehyde = cinnamon.
Tro's Introductory Chemistry, Chapter 18

134. Ketone Odors and Flavors
Acetophenone = pistachio.
Carvone = spearmint.
Ionone = raspberries.
Muscone = musk.
Tro's Introductory Chemistry, Chapter 18

135. Naming Aldehydes and Ketone
Make part of main chain.
Number from end closest to carbonyl.
Precedence over OH group.
For aldehyde, change ending to -al.
Always position 1, no number necessary.
For ketone, change ending to -one.
Indicate position on chain with number in front of base name.
4-hydroxybutanal
4-hydroxy-3-hex-1-enone
Tro's Introductory Chemistry, Chapter 18

136. Practice—Name the Following:
Tro's Introductory Chemistry, Chapter 18
136

137. Practice—Name the Following, Continued:
3-methylbutanal
2-methyl-3-pentanone
Tro's Introductory Chemistry, Chapter 18
137

138. Tro's Introductory Chemistry, Chapter 18
Carboxylic Acids
RCOOH.
Sour tasting.
Weak acids.
Citric acid.
Found in citrus fruit.
Ethanoic acid = acetic acid.
Vinegar.
Methanoic acid = formic acid.
Insect bites and stings.
Tro's Introductory Chemistry, Chapter 18

139. Carboxylic Acids, Continued
Made by the oxidation of aldehydes and alcohols.
OH on the end of the chain.
Always on main chain.
Has highest precedence.
C of group always C1.
Position not indicated in name.
Change ending to -oic acid.
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140. Tro's Introductory Chemistry, Chapter 18
Naming Acids
Main chain always contains COOH group.
C of COOH group always Cl.
Position not indicated in name.
Give base name -oic acid ending.
3-hydroxy-3-methylpentanoic acid
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140

141. Practice—Name the Following:
Tro's Introductory Chemistry, Chapter 18
141

142. Practice—Name the Following, Continued:
3-methyl-3-butenoic acid or
3-methylbut-3-enoic acid
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142

143. Tro's Introductory Chemistry, Chapter 18
Esters
R–COO–R.
Sweet odor.
Made by reacting carboxylic acid with an alcohol.
RaCOOH + RbOH  RaCOORb + H2O
Name alkyl group from alcohol, then acid name with -ate ending.
Precedence over carbonyls, but not carboxylic acid.
Number from end with ester group.
Aspirin
Tro's Introductory Chemistry, Chapter 18

144. Naming Esters Main chain always contains COOR group.
Unless acid group also present.
C of COOR group on C1.
Position not indicated in name.
Start by naming R group as alkyl group.
No position number.
Always listed first, even if other groups on chain.
Change ending on base name to -oate.
methyl-4-isopropylbenzoate
144

145. Naming Esters, Continued
Tro’s Introductory Chemistry, Chapter 18

146. Practice—Name the Following:
Tro's Introductory Chemistry, Chapter 18
146

147. Practice—Name the Following, Continued:
isopropyl-3-phenylbutanoate
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147

148. Tro's Introductory Chemistry, Chapter 18
Amines
N containing organic molecules.
Very bad smelling.
Form when proteins decompose.
Organic bases.
Name alkyl groups attached to the N, then add -amine to the end.
Putrescine
Ethylamine
Ethylmethylamine
Cadaverine
Tro's Introductory Chemistry, Chapter 18

149. Draw a Structural Formula for Diethylamine.
Tro's Introductory Chemistry, Chapter 18
149

150. Draw a Structural Formula for Diethylamine, Continued.
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150

151. Tro's Introductory Chemistry, Chapter 18
Amines
Many amines are biologically active.
Dopamine—a neurotransmitter.
Epinephrine—an adrenal hormone.
Pyridoxine—vitamin B6.
Alkaloids are plant products that are alkaline and biologically active.
Toxic.
Coniine from hemlock.
Cocaine from coca leaves.
Nicotine from tobacco leaves.
Mescaline from peyote cactus.
Morphine from opium poppies.
Tro's Introductory Chemistry, Chapter 18

152. Identify the Functional Groups in Each.
CH3CH2COOCH3.
(CH3CH2)2NH.
CH3CHCHCH2CHO. O H C O 3
Tro's Introductory Chemistry, Chapter 18

153. Identify the Functional Groups in Each, Continued.
CH3CH2COOCH3.
(CH3CH2)2NH.
CH3CHCHCH2CHO.
Ester
Ester O
Ketone
and
ether
Amine
Acid,
aromatic
ring,
ether H C O 3
Double bond
and aldehyde

154. Tro's Introductory Chemistry, Chapter 18
Polymers
Tro's Introductory Chemistry, Chapter 18
154

155. Tro's Introductory Chemistry, Chapter 18
Macromolecules
Polymers are very large molecules made by repeatedly linking together small molecules.
Monomers.
Natural.
Modified natural polymers.
Synthetic.
Plastics, elastomers (rubber), fabrics, adhesives.
Composites.
Additives such as graphite, glass, metallic flakes.
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156. Tro's Introductory Chemistry, Chapter 18
Natural Polymers
Polysaccharides.
Cellulose (cotton).
Starch.
Proteins.
Nucleic acids (DNA).
Natural latex rubber, etc.
Shellac.
Amber, lignin, pine rosin.
Asphalt, tar.
Tro's Introductory Chemistry, Chapter 18

157. Modified Natural Polymers
Cellulose acetate.
Rayon.
Film.
Vulcanized rubber.
Gun cotton.
Celluloid.
Ping-pong balls.
Gutta percha.
Fill space for root canal.
Casein.
Buttons, moldings, adhesives.
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158. Polymers

159. Tro's Introductory Chemistry, Chapter 18
Polymerization
The process of linking the monomer units together.
Two process are addition polymerization and condensation polymerization.
Monomers may link head to tail, head to head, or tail to tail.
Head-to-tail linking is most common.
Regular pattern gives stronger attractions between chains than random arrangements.
Tro's Introductory Chemistry, Chapter 18

160. Head to tail Head to head, tail to tail Cl C H H C Cl Head Tail Head

161. Addition Polymerization
Monomers add to the growing chain in such a manner that all the atoms in the original monomer wind up in the chain.
No other side products formed, no atoms eliminated.
First monomer must “open” to start reaction.
Done with heat or addition of an initiator.
Chain reaction.
Each added unit ready to add another.
Tro's Introductory Chemistry, Chapter 18

162. Addition Polymerization, Continued
initiator
etc.
initiator C H Cl • Cl C H + • Cl C H + •

163. Condensation Polymerization
Monomer units are joined by removing small molecules from the combining units.
Polyesters, polyamides lose water.
No initiator needed.
Chain reaction.
Each monomer has two reactive ends, so chain can grow in two directions.
Tro's Introductory Chemistry, Chapter 18

164. Condensation Polymerization, Continued+ C O H + H O C 2 H C O 2
+ H2O
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165. Tro's Introductory Chemistry, Chapter 18
Plastics
Material capable of being molded or shaped.
Round, hard balls; thin, flexible threads; intricate molds; or flat sheets.
Molar mass 10,000 to 1,000,000 amu.
Many are in “glass” or amorphous solid state.
Solid that has semi-fluid characteristics.
Glass transition temperature.
Do not melt like an ice cube.
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166. Plastic Characteristics
Transparent or translucent.
Chemical resistance.
Thermal and electrical insulators.
Low density.
Varying strengths.
Kevlar.
Mold or extrude.
Elasticity.
Regain original shape if quick stress applied.
Foamed.
Tend to soften when heated.
Rather than quickly melt.
Tro's Introductory Chemistry, Chapter 18

167. Synthetic Polymers Polyethylene Polypropylene Polyvinyl chloride
HDPE
LDPE
Polypropylene
Polyvinyl chloride
Polyesters
polyethylene terephthalate
Polyamides
nylon
Kevlar

168. Polyethylene Terephthalate (PET)1
Condensation copolymer of ethylene glycol + terephthalic acid.
A polyester.
Transparent.
High-impact strength.
Nonreactive with acid and atmospheric gases.
Doesn’t stretch.
Used for soda bottles, Dacron, Mylar. C O H
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169. High Density Polyethylene (HDPE)2
Addition polymer with linear chains.
Opaque.
Denser than LDPE.
Mechanically stronger than LDPE.
More rigid than LDPE.
More crystalline.
Higher heat resistance than LDPE.
Nonreactive to acids and bases.
Absorbs oils and softens.
Oxidizes on exposure to air and sunlight.
Subject to cracking.
Used for containers, caps, bullet-proof vests, synthetic ice.
H H
C C
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170. Poly Vinyl Chloride (PVC)3
Addition polymer.
Transparent to opaque.
Flame resistant.
Low heat resistance.
Good chemical resistance.
High-impact strength.
Quite rigid.
Many additives used to modify properties.
Plasticizer adds flexibility.
Used in food wrap, pipes, flooring and wall covering, toys, hoses, auto trim, squeeze tubes, and appliance housings.
H Cl
C C
H H
Tro's Introductory Chemistry, Chapter 18

171. Low Density Polyethylene (LDPE)4
Addition polymer with branched chains.
Lower density, strength, heat resistance (100–125 °C), and rigidity than HDPE.
Used in food, trash, and grocery bags as well as in electrical wire insulation.
H H
C C
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172. Tro's Introductory Chemistry, Chapter 18
Polypropylene (PP) 5
Addition polymer.
Opaque.
High-stretching strength.
High heat resistance (170 °C).
Excellent chemical resistance.
Flexed almost indefinitely without tearing.
Smooth surface with high luster.
Used in carpets and upholstery; chemical resistant pipes, containers, and tanks; margarine tubs; and medicine bottles.
H CH3
C C
H H
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173. Tro's Introductory Chemistry, Chapter 18
Polystyrene (PS) 6
Addition polymer.
Low-impact resistance.
Fair strength and stiffness.
Poor chemical resistance.
Transparent, glassy, sparkling clarity.
Moderate heat resistance (90 °C).
Model cars, computer housing, Styrofoam, clear drinking cups, and hard-molded parts. H C
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174. Tro's Introductory Chemistry, Chapter 18
Acrylics
Polymethylmethacrylate, PMMA.
Low-impact resistance.
Good strength and stiffness.
Excellent transparency.
Excellent scratch resistance.
Moderate heat resistance.
Addition polymer of methyl methacrylate.
Uses include Plexiglas, Lucite, lighting fixtures, lenses, fiber optic filament, appliance faceplates, decorative signs, and paints.
Also, reduces oil viscosity. 3 C H O
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175. Tro's Introductory Chemistry, Chapter 18
Polycarbonates (PC)
Excellent physical properties.
Excellent toughness.
Very good heat resistance.
Fair chemical resistance.
Transparent.
Condensation copolymer of Bisphenol A and phosgene.
Lexan, Calibre , Makrolon , Panlite .
Used in equipment housings, exterior auto parts, outdoor light fixtures, non-auto vehicle windows, structural parts, medical supply parts, scratch-resistant coatings, eye wear, bullet–proof glass, and DVDs. C H 3 O
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176. Tro's Introductory Chemistry, Chapter 18
Nylon
Condensation copolymer of a diamine with a diacid.
Polyamides.
Nylon 6,6 made by condensing 1,6–hexandiamine, H2N–(CH2)6–NH2, with hexandioic acid, HOOC–(CH2)4–COOH.
Good physical properties.
Effected by moisture.
Very good heat resistance.
Excellent chemical resistance.
Excellent wear resistance. ( C H 2 ) 6 N O 4
Tro's Introductory Chemistry, Chapter 18