1. Organic Chemistry Organic Chemistry: The chemistry of carbon
and carbon-based compounds
Organic Chemistry in everyday life:
Smells & tastes: fruits, chocolate, fish, mint
Medications: Aspirin, Tylenol, Decongestants, Sedatives
Addictive substances: Caffeine, Nicotine, Alcohol, Narcotics
Hormones/Neurotransmitters: Adrenaline, Epinephrine
Food/Nutrients: Carbohydrates, Protein, Fat, Vitamins
Genetics: DNA, RNA
Consumer products: Plastics, Nylon, Rayon, Polyester

2. Drawing Organic Structures
Shortcuts make structures easier & faster to draw
Butane: C4H10
Lewis Structure
Carbon Atoms
Line Structure
Only shows bonds
C atoms assumed at each end and intersection of bonds
H atoms not shown
Assume 4 bonds to each C
Fulfill C’s 4 bonds by adding H’s
Condensed Structures
CH3CH2CH2CH3
CH3(CH2)2CH3

3. Types of Organic Compounds
Classified according to functional group
Alkane
Alkene
Alkyne
Haloalkane
Alcohol
Ether
Ketone
Aldehyde
Carboxylic acid
Amine
Amino acid
Amide

4. Big Idea in Organic Chemistry
Structure controls Function
Each functional group has predictable reactivity

5. Alkanes or Paraffins
All C atoms are tetrahedral and sp3 hybridized (only C-C single bonds)
General formula = CnH2n+2 (CH4, C2H6, C3H8, C4H10, etc.)
Can have linear or branched alkanes
C5H12 1° 3° 2°
Same molecular formula, different structure: structural isomers
Branches are called substituents
Primary (1°) carbon atom: bound to one other C atom
Secondary (2°) C atom: bound to 2 other C atoms
Tertiary (3°) C atom: ” 3 ”
Quaternary (4°) C atom: ” 4 ”

6. Names of Linear Alkanes and Alkyl Substituents
C atoms
Alkane
Alkyl substituents 1 2 3 4 5 6 7 8 9 10
CH4
CH3CH3
CH3CH2CH3
CH3CH2CH2CH3
Methane
Ethane
Propane
Butane
Pentane
Hexane
Heptane
Octane
Nonane
Decane
-CH3
-CH2CH3
-CH2CH2CH3
Methyl
Ethyl
Propyl
etc.
Root: number of C atoms
Suffix: functional group
(-ane for alkanes)
(-yl for alkyl groups)

7. H C C H
Methane
CH4
Butane
C4H10 H C ? C H ? R R
Methyl
-CH3
Butyl
-C4H9
Where R = any other C atom or arrangement of C atoms

8. First Ten Hydrocarbons: Properties
Number of
Carbon Atoms
Molecular
Formula
Melting
Point, oC
Boiling
Point, oC
# of
Isomers
Name
Methane
Ethane
Propane
Butane
Pentane
Hexane
Heptane
Octane
Nonane
Decane 1 2 3 4 5 6 7 8 9 10
CH4
C2H6
C3H8
C4H10
C5H12
C6H14
C7H16
C8H18
C9H20
C10H22
-182.5
-183.2
-187.7
-138.3
-129.7
95.3
90.6
56.8
53.6
29.7
-161.5
-88.6
-42.1
-0.5
36.1
68.7
98.4
125.7
150.8
174.0 1 2 3 5 9 18 35 75

9. Nonpolar → only London Dispersion Forces IMF
Properties of Alkanes
Nonpolar → only London Dispersion Forces IMF
Larger molecular weight → Stronger London dispersion forces
Compound
Methane
Ethane
Propane
Butane
Pentane
Formula
CH4
C2H6
C3H8
C4H10
C5H12 MW 16 30 44 58 72
Boiling point (°C)
-164
-88.6
-42.1
-0.5
+36.0
Linear Alkanes:
1 - 4 C atoms: gas at room temp
C atoms: liquid at room temp
>15 C atoms: solid at room temp

10. Fractional Distillation of Crude Oil
Kelter, Carr, Scott, Chemistry A World of Choices 1999, page 429

11. Naming Branched Alkanes (IUPAC)
Octane
4-ethyl 6 2 8
4-ethyl-3,5-dimethyloctane 5 4 7 3 1
3-methyl and 5-methyl
= 3,5-dimethyl
Root name: name of longest continuous C chain (parent chain)
2 equally long? Choose the one with more branches
Number C atoms in chain, starting at end with first branch
Identify substituents, give each a number (C it is connected to)
Two or more identical substituents: use prefixes (di-, tri-, tetra-, etc.)
List substituents alphabetically before root name
Do not alphabetize prefixes
Punctuation: commas separate numbers from each other
hyphens separate numbers from names
no space between last substituent & root name

12. Common Names of other Alkyl Substituents
Remember that R = any carbon chain R
3 carbons R
isopropyl
alphabetized as “i”
“iso” indicates symmetry R R
isobutyl
alphabetized as “i”
4 carbons 2o R R 2o
sec-butyl
alphabetized as “b”
Secondary carbon R 3o 3o R
tert-butyl
alphabetized as “b”
Tertiary carbon

13. Naming Practice C H 2 - methylbutane butane Expanded Structure
Line Structure H C
2 - methylbutane
butane

14. Naming Practice H H CH3 H C C C H H C H H C H H C H H 4,4-dimethyl
Line Structure 1 2 3 4 5 6 4 5 6 H H C H H C H H C H H
4,4-dimethyl
hexane
3,3-dimethyl
hexane
Lowest sum of numbers
is correct

15. Isomers
The fat dog shook himself, and then rolled over on the wet rug. OR
The dog shook the fat rug, then rolled over and wet on himself.
These two statements use the same words...
but have very different meanings!
Likewise, isomers may have the same formula, but have very different structures…

16. Structural Isomers of C4H10
2-methylpropane or

17. Structural Isomer Practice
On piece of your own paper, draw AND name ALL of the isomers for the following alkanes:
Formulas
# isomers
Pentane
Hexane
Heptane
C5H12
C6H14
C7H16 3 5 9
Some of your drawings may look different, but they are only different structures (isomers) if they also have different names
If you complete that, try to draw and name all of the isomers for octane (C8H18). There are 18 of them!

18. Structural Isomers: Pentane (C5H12)
2-methylbutane
2,2-dimethylpropane

19. Structural Isomers: Hexane (C6H14)
2,3-dimethylbutane
2-methylpentane
2,2-dimethylbutane
3-methylpentane

20. Structural Isomers: Heptane (C7H16)
2,2-dimethylpentane
2-methylhexane
2,3-dimethylpentane
3-methylhexane

21. Structural Isomers: Heptane (C7H16)
2,4-dimethylpentane
3-ethylpentane
3,3-dimethylpentane
2,2,3-trimethylbutane

22. Comparing Structural Isomers
(Same formula, different structure)
C5H12
Structure
Name
Boiling point (°C)
pentane
36.0
2-methylbutane
27.9
2,2-dimethylpropane
9.5
More branching → weaker London dispersion forces
BP/MP of Linear alkanes > BP/MP of branched alkanes

23. Chemical Bingo: Naming Review
There are 27 structures or names drawn on the next slide. Select 24 of them to be placed on your bingo card.
Because of space issues, I would number each bingo square and then list the names or structures on a separate sheet of paper
If I give you a name, you must match it to a structure. If I give you a structure, you must match it to a name
Any bingo winner will be awarded 1 bonus point on the quiz (5% pts)

24. Chemical Bingo: Alkanes
isopropyl sec-butyl
tert-butyl isobutyl
decane nonane
2,3,4,5-tetramethylhexane
3,4-diethylhexane
3,5-diethyl-4-isopropylheptane
4-tert-butyl-3,5-dimethylheptane
4-ethyl-2,2,3,5,6,6-hexamethylheptane
Any isomer of C5H12
Any isomer of C6H14
Any isomer of C7H16

25. Reactions of Alkanes 13/2 4 5 9/2 4 5 Combustion
exothermic reaction
alkanes used as fuel source
13/2 4 5
C4H10 + ___ O2  ___ CO2 + ___ H2O
Incomplete Combustion with insufficient O2 produces CO
Poor ventilation, cigarettes
9/2 4 5
C4H10 + ___ O2  ___ CO + ___ H2O
CO is poisonous because it binds to the hemoglobin in the blood, preventing the absorption of O2

26. Radical Halogenation Terms
Mechanism
How the reaction occurs through multiple steps (most reactions actually occur in many steps)
Chain Reaction
Reactions that occur on their own after some initiating event
Free Radicals
Atoms that have one free electron—highly reactive

27. Radical Halogenation Terms
Mechanism
How the reaction occurs through multiple steps (most reactions actually occur in many steps)
Chain Reaction
Reactions that occur on their own after some initiating event
Free Radicals
Atoms that have one free electron—highly reactive (denoted with a dot next to atom)

28. Radical Halogenation Terms
Initiation Step
Step where a bond is split by heat/light, producing free radicals
Propagation Step
Step where free radicals react with non-radicals, producing more free radicals and continuing the “chain reaction”
Termination Step
Step where free radicals react with each other, producing non-radicals and terminating the “chain reaction”

29. Radical Halogenation Terms
Initiation Step
Step where a bond is split by heat/light, producing free radicals
Propagation Step
Step where free radicals react with non-radicals, producing more free radicals and continuing the “chain reaction”
Termination Step
Step where free radicals react with each other, producing non-radicals and terminating the “chain reaction”

30. Radical Halogenation of Alkanes
Reactions of Alkanes
Radical Halogenation of Alkanes
CH4 + Cl2  CH3Cl + HCl
Mechanism (chain reaction):
Step 1 Cl2 ⇌ Cl· + Cl ·
Step 2 Cl· + CH4  CH3· + HCl
Step 3 CH3· + Cl2  CH3Cl + Cl·
Step 4 Cl· + Cl·  Cl2
Type of Step h
Initiation
Propagation
Termination
(Free Radicals)
Overall reaction: CH4 + Cl2  CH3Cl + HCl
 chloromethane
Why not 1-chloromethane?
Halogenated product is a haloalkane
Naming: halogen atom is a substituent, replace –ine ending with –o
-F fluoro -Cl chloro -Br bromo -I iodo

31. Radical Halogenation of Alkanes
Halogen substitutes for hydrogen in alkane →multiple results
Cl2 
Cl2 
Cl2 
Cl2 
CH4
CH3Cl
CH2Cl2
CHCl3
CCl4
Compound
CH3Cl
CH2Cl2
CHCl3
CCl4
IUPAC Name
Chloromethane
Dichloromethane
Trichloromethane
Tetrachloromethane
Common Name
Methyl chloride
Methylene chloride
Chloroform
Carbon tetrachloride
All are liquids at room temperature
Heavy Cl atoms increase LDF
Polar C-Cl bonds – can have polar molecules

32. Chemistry: An Intro to General, Organic and Biological Chemistry
Textbook Resource
Chemistry: An Intro to General,
Organic and Biological Chemistry
by Timberlake (Green/Tan Book)
Sections already covered
Currently Section 11.2 (Haloalkanes)
Can be used as an outside reference

33. Naming Practice: Haloalkanes
Two equal numbering options? Number based on alpha order 1 2 3 4 5 6 1 2 3 4 5 6
5-chloro-2-fluorohexane
2-chloro-5-fluorohexane
2-chloro-4-fluoro-2,3-dimethylpentane
2-bromo-3-ethyl-4-iodopentane
2-bromo-4-chloro-3-isopropylpentane

34. Radical Halogenation: Predict the Product?
+ Cl2 →
+ HCl OR ? ?
1-chloropropane
2-chloropropane OR
3-chloropropane?
Remember that any H on the alkane can be replaced by a halogen
+ Br2 → OR
1-bromo-2-methylbutane
2-bromo-2-methylbutane

35. Radical Halogenation: Predict the Product
+ Br2 → OR
1-bromo-2-methylbutane
2-bromo-2-methylbutane OR OR
2-bromo-3-methylbutane
1-bromo-3-methylbutane
1-bromo-2-methylbutane

36. Structural Isomers What are the possible structural isomers of C3H7Br?
1-bromopropane
2-bromopropane
What are the possible structural isomers of C4H9Cl?
1-chlorobutane
2-chloro-2-methylpropane
2-chlorobutane
1-chloro-2-methylpropane

37. Structural Isomer Practice
On piece of your own paper, draw AND name ALL of the isomers with the following formulas:
Formulas
# isomers
C4H9I
C3H6Cl2
C5H11Br
C4H8Cl2 4 8 9
To be honest, there may be more…this is what I found, so try and prove me wrong! Extra Credit to anyone who can find more structures…
Some of your drawings may look different, but they are only different structures (isomers) if they also have different names

38. Structural Isomers: C4H9I
1-iodobutane
2-iodobutane I I
2-iodo-2-methylbutane
1-iodo-2-methylbutane

39. Structural Isomers: C3H6Cl2
1,1-dichloropropane
1,2-dichloropropane
1,3-dichloropropane
2,2-dichloropropane

40. Structural Isomers: C5H11Br
1-bromopentane
2-bromopentane
3-bromopentane
1-bromo-3-methylpentane

41. Structural Isomers: C5H11Br
1-bromo-2-methylbutane
2-bromo-3-methylbutane
1-bromo-2,2-dimethylbutane
2-bromo-2-methylbutane

42. Structural Isomers: C4H8Cl2
1,1-dichlorobutane
1,2-dichlorobutane
1,3-dichlorobutane
1,4-dichlorobutane

43. Structural Isomers: C4H8Cl2
1,1-dichlorobutane
1,2-dichloro-2-methylpropane
2,2-dichlorobutane
1,3-dichloro-2-methylpropane
2,3-dichlorobutane

44. Halogenation Reaction Byproduct
CH4 + X2 → CH3X + HX where X = any halogen
Technically, any halogenation reaction will also produce HX as a byproduct (HCl, HBr, etc.)
However, we are not concerned with this byproduct and thus ignore it