Organic Chemistry
(the study of carbon-containing compounds)
Carbon atoms have unique properties that allow them to form many compounds:
1. Carbon atoms form 4 covalent bonds.
2. Carbon atoms link together to form chains and rings of different sizes.
3. Carbon atoms form single, double, and triple bonds.
Hydrocarbons – organic compounds that contain only carbon and hydrogen
Representing Hydrocarbons:
1. Molecular formula
2. Complete structural formula
 shows all atoms, all bonds
3. Condensed structural formula
 C-H bonds (and possibly C-C bonds) are understood
4. Condensed structural formula
 C-H bonds and C-C bonds are understood
5. Skeleton structural formula
 carbon skeleton; all hydrogens and C-H bonds are understood
6. Line structural formula
 carbons, hydrogens and all bonds are understood
 the end of each straight line, and the points at which the lines meet, represent carbon
atoms
ALKANES
The simplest hydrocarbons are called alkanes; they contain only single covalent bonds (C-C) and C-H).
Type of alkanes:
a) Continuous-Chain Alkanes: contain any number of carbon atoms in a straight chain.
Ex 1: Ethane (C2H6)
Ex 2: Butane (C4H10)
The ten simplest continuous-chain alkanes: (KNOW THIS!!!!)
number of carbons
1
methane
CH4
ethane
CH3-CH3
2
propane
CH3-CH2-CH3
3
butane
CH3-CH2-CH2-CH3
4
pentane
CH3-CH2-CH2-CH2-CH3
5
hexane
CH3-CH2-CH2-CH2-CH2-CH3
6
heptane
CH3-CH2-CH2-CH2-CH2-CH2-CH3
7
octane
CH3-CH2-CH2-CH2-CH2-CH2-CH2-CH3
8
nonane
CH3-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3
9
decane
CH3-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH2-CH3
10
b) Branched-Chain Alkanes:
Sometimes an atom or group of atoms can replace a hydrogen in an alkane
If the substituent is another hydrocarbon, it is called an alkyl group.
When an alkyl group is attached to a parent chain, it creates a branched-chain alkane.
Names of alkyl groups are based on the alkane name but end in ‘-yl’
methyl
ethyl
propyl
-CH3
-CH2-CH3
-CH2-CH2-CH3
ETC.
Example:
Naming Branched-Chain Alkanes:
1. Find and name the longest continuous chain of carbon atoms (the main chain). It is not necessary
that the longest chain be written either horizontally or in a straight line. This is the parent chain.
2. Identify alkyl groups attached to the main chain and name them.
3. Number the carbons in the parent chain to give the position of each branch (begin from the end
that gives them the lowest numbers possible).
4. Name the alkane by writing:
 the name of the branches with their corresponding carbon numbers, in alphabetical order
 the name of the parent chain
NOTES:
 use prefixes if an alkyl group appears more than once (di, tri, tetra, penta, etc.
 don’t alphabetize the prefixes
 use commas to separate any numbers
 use hyphens to separate numbers and words
 If chains of equal length are competing for selection as the main chain, choose the chain which has
the greatest number of alkyl groups
Naming 1-branch alkanes:
Ex 1:
Ex 2:
Name the following alkanes:
1.
2.
3.
4.
Naming alkanes with multiple branches:
Ex 1:
Ex 2:
Ex 3:
Name the following alkanes:
1.
2.
3.
4.
5.