1. Simple Organic Chemistry
Basic Structure and Nomenclature
Adapted from

2. Condensed Structural Formula = CH3(CH2)nCH3
First Ten Alkanes
Formula
Name
CH4
Methane
C6H14
Hexane
C2H6
Ethane
C7H16
Heptane
C3H8
Propane
C8H18
Octane
C4H10
Butane
C9H20
Nonane
C5H12
Pentane
C10H22
Decane
Alkane = CnH2n+2
Condensed Structural Formula = CH3(CH2)nCH3

3. Straight Chain Alkanes aren’t “Straight”
C – C bonds are sp3 hybridized
Butane, C4H10
Decane, C10H22

4. Rules for Naming Alkanes (Nomenclature)
1. For a branched hydrocarbon, the longest continuous chain of carbon atoms gives the root name for the hydrocarbon 1 2 3 4
4 carbon chain = butane

5. Rules for Naming Alkanes (Nomenclature)
2. When alkane groups appear as substituents, they are named by dropping the -ane and adding -yl.
—CH3 Methyl
—CH2CH3 Ethyl
—CH2CH2CH3 Propyl
—CH2CH2CH2CH3 Butyl
Methyl

6. Rules for Naming Alkanes (Nomenclature)
3. The positions of substituent groups are specified by numbering the longest chain of carbon atoms sequentially, starting at the end closest to the branching. 1 2 3 4
Methyl

7. Rules for Naming Alkanes (Nomenclature)
4. The location and name of each substituent are
followed by the root alkane name. The substituents
are listed in alphabetical order (irrespective of any
prefix), and the prefixes di-, tri-, etc. are used to
indicate multiple identical substituents. 1 2 3 4
Name:
2-methylbutane
Methyl

8. Nomenclature Practice
Name this compound 1
9 carbons = nonane 2 4 3 5 6 7 8 9
Step #1: For a branched hydrocarbon, the longest continuous chain of carbon atoms gives the root name for the hydrocarbon

9. Nomenclature Practice
Name this compound
9 carbons = nonane 1 2 4 3 5 6
CH3 = methyl 7
chlorine = chloro 8 9
Step #2: When alkane groups appear as substituents, they are named by dropping the -ane and adding -yl.

10. Nomenclature Practice
Name this compound
9 carbons = nonane 1 2 4 3 5 6
CH3 = methyl 7
chlorine = chloro 8 9 1 9
NOT 9 1
Step #3: The positions of substituent groups are specified by numbering the longest chain of carbon atoms sequentially, starting at the end closest to the branching.

11. Nomenclature Practice
Name this compound
9 carbons = nonane 1 2 4 3 5 6
CH3 = methyl 7
chlorine = chloro 8 9
2-chloro-3,6-dimethylnonane
Step #4: The location and name of each substituent are followed by the root alkane name. The substituents are listed in alphabetical order (regardless of any prefix), and the prefixes di-, tri-, etc. are used to indicate multiple identical substituents.

12. Cyclic Alkanes Cyclopropane, C3H6 Cyclobutane, C4H8
Cyclopentane, C5H10
Cyclohexane, C6H12
Cycloheptane, C7H14
Remember, explicit hydrogens are left out

13. Structural Isomers
Isomers are molecules with the same chemical formula, but different organization of atoms (different bonding)
n-Pentane, C5H12
2-methylbutane, C5H12
2,2-dimethylpropane, C5H12

14. Alkenes Contain Carbon-Carbon Double bonds
Each carbon is
sp2 hybridized
Ethene
1  bond
Alkenes are considered unsaturated

15. Geometric Isomerism in Alkenes
Unhybridized p orbitals must align, so bond cannot rotate
cis-2-butene trans-2-butene

16. Alkynes Contain Carbon-Carbon Triple Bonds
Each carbon is
sp hybridized
Ethyne
1  bond
1  bond
Alkynes are considered unsaturated

17. Reactions of Alkenes and Alkynes
Hydrogenation
Propene
Propane
Dehydrogenation
Ethane
Ethene
Polymerization
Small molecules are joined together to form a large molecule
Polyethylene

18. Reactions of Alkenes and Alkynes
Combustion
Propane
Halogenation
1-Pentene
1-2-dibromopentene
Substitution

19. Aromatic Hydrocarbons
Cyclic unsaturated hydrocarbons with
delocalized electrons
The simplest aromatic hydrocarbon is
benzene (C6H6)
OR…

20. Geometric Isomerism in Aromatics
ortho (o-) = two adjacent
substituents
o-dichlorobenzene
meta (m-) = one carbon between
substituents
m-dichlorobenzene
para (p-) = two carbons between
substituents
p-dichlorobenzene

21. Hydrocarbon Derivatives
Class
Functional Group
General Formula
Alcohol
hydroxyl group O — H
R – OH
Alkyl halide
— X
R — X
Ether
— O —
R — O — R’
Aldehyde
carbonyl group O ||
— C — H O
R — C — H
Ketone
— C —
R — C — R’
Carboxylic acid
carboxyl group O
— C — OH
Ester
— C — O—
R — C — O — R’
Amine
amine group |
—N— R’
R — N — R’’

22. Alcohols
-OH group
Higher than expected boiling point (based on molecular weight)
Naming is based on longest carbon chain attached to –OH group
End in -ol

23. Aldehydes & Ketones -al -one
No numbers used for naming aldehydes since group is always on terminal carbon

24. Carboxylic Acids & Esters
Carboxylic acids are weak acids
Examples: acetic, salicylic
Esters have a fragrant, often pleasant odor
Esterification:

25. Amines (-NH2)
Derivatives of ammonia where one or more N-H bond is replaced by N-C bond
Figure shows the structures of the 20 amino acids