Organic Chemistry
I.
Carbon
A. Organic Compounds = contain carbon
– Exceptions: oxides and carbonates
B. Carbon has 4 valence electrons, and
therefore forms 4 covalent bonds
– 4 single bonds:
– At least 1 double bond:
– 1 triple bond with 1 single bond:
C. Bond Length and Strength in Organic
Compounds
1. Single bonds are longest, double bonds are
shorter than single, and triple bonds are shortest
2. Single bonds are weakest, double bonds are
stronger than single, and triple bonds are
strongest
II. Hydrocarbons
A. Hydrocarbon compounds contain only
carbon and hydrogen
1. Saturated hydrocarbons - all carbon-carbon
bonds are single bonds (allows for maximum # of
hydrogens)
2. Unsaturated hydrocarbons - containing carboncarbon multiple (double/triple) bonds (minimizes
the # of hydrogens
B. Types of Hydrocarbons
1. Alkanes – saturated; contain only single C-C bonds
Chemical Formula:
Structural Formula:
2. Alkenes – unsaturated; contain at least 1 double
bond between adjacent carbon atoms
Chemical Formula:
Structural Formula:
3. Alkynes – unsaturated; contain at least 1 triple
bond between adjacent carbon atoms
Chemical Formula:
Structural Formula:
III. Alkanes
A. Isomers of Alkanes
1. Structural Isomers - Same formula, but the atoms
are bonded together in a different order
• Alkanes can form straight or bent chains
(unbranched chains)
• Alkanes can also form branched chains
C4H10 Butane
C4H10 2-methylpropane
B. Formulas for Alkanes
C. Naming Alkanes
Prefix
MethEthPropButPentHexHeptOctNonDec-
# of Carbons
1
2
3
4
5
6
7
8
9
10
Suffix
-ane
Type of bond
single bonds
C. Naming Alkanes (cont)
1. Other rules:
• For branched hydrocarbons use the longest
continuous chain for the root name.
• Alkanes missing one H atom can have another
hydrocarbon attached at the missing H point.
• Specify the names of substituents by
numbering the C atoms starting at the end
closest to the branching.
• If a substituent occurs more than once use a
prefix to show this.
CH3
CH2
CH2
CH
CH2
CH3
CH2
CH3
D. Petroleum
1. Petroleum – thick, dark liquid composed mostly
of hydrocarbon compounds
2. Natural gas – consists mostly of methane,
usually associated with petroleum deposits
3. To be used, petroleum must be separated by
boiling into fractions.
4. Pyrolytic Cracking – heavier
molecules of kerosene fraction
are
heated to 700oC, causing the
fractions to break (crack) into
gasoline fractions
IV. Alkenes & Alkynes
A. Naming Alkenes & Alkynes
1. Same rules for alkanes apply to alkenes & alkynes
2. Endings are different, and number the 1st carbon
involved in the double/triple bond
3. Alkenes end in –ene; Example: 1-butene
4. Alkynes end in –yne; Example: 2-butyne
B. Aromatic Hydrocarbon
1. Aromatic hydrocarbons – cyclic unsaturated
hydrocarbons with strong aromas
2. Benzene – simplest aromatic hydrocarbon
C. Isomers of Alkenes & Alkynes
1. Geometric Isomers: Isomers in which the order
of atom bonding is the same but the
arrangement of atoms in space is different
Cis 1,2-dichloroethane Trans 1,2-dichloroethane
2. Enantiomers: mirror images of each other