1. Functional Groups
Unit 3

2. Hydrocarbons There are four basic types of hydrocarbons: Alkanes
Alkenes
Alkynes
Aromatic hydrocarbons

3. Functional Groups
The term functional group is used to refer to parts of organic molecules:
an atom or group of atoms within a molecule that shows a characteristic set of physical and chemical properties
important for three reasons; they are
1. the units by which we divide organic compounds into classes
2. the sites of characteristic chemical reactions
3. the basis for naming organic compounds

4. Hydrocarbon Derivatives
There are millions of organic compounds.
We can categorize them into classes of compounds.
Each of the classes has a specific functional group. A functional group is a set of atoms that gives a class of compounds its characteristics.
There are 10 classes: five without a carbonyl group and five with a carbonyl group (C=O).

5. Non-Carbonyl Hydrocarbon Derivatives
Here are the basic hydrocarbon classes. R is an alkyl group and Ar is an aryl group.

6. Carbonyl Hydrocarbon Derivatives

7. Organic Halides
If a halogen atom (F, Cl, Br, I) replaces a hydrogen atom in a hydrocarbon, the new compound is an organic halide.
Organic halides are used primarily as household and industrial solvents.
They are found in many pesticides.
They are essentially nonpolar molecules with low boiling points and properties similar to those of alkanes.

9. Alcohols & Phenols contain an -OH (hydroxyl) group
Ethanol may also be written as a condensed structural formula
When an –OH replaces a hydrogen atom on a arene, the resulting molecule is a phenol

10. Alcohols
alcohols are classified as primary (1°), secondary (2°), or tertiary (3°) depending on the number of carbon atoms bonded to the carbon bearing the -OH group C H 3 - O A 1 a l c o h 2

11. Alcohols
there are two alcohols with molecular formula C3H8O

12. Thiols
A thiol is an organosulfur compound that contains a carbon-bonded sulfhydryl (–C–SH or R–SH) group
The functional group of a thiol is an SH (sulfhydryl) group
The –SH functional group itself is referred to as either a thiol group or a sulfhydryl group

13. Ethers & Epoxides
The functional group of an ether is an oxygen atom bonded to two carbon atoms
Ethers tend to be quite unreactive. Therefore, they are good polar solvents.
Epoxide: a cyclic ether in which oxygen is one atom of a three-membered ring

14. Amines
contain an amino group; an sp3- hybridized nitrogen bonded to one, two, or three carbon atoms
an amine may by 1°, 2°, or 3° C H 3 N
Methylamine
(a 1° amine)
Dimethylamine
(a 2° amine)
Trimethylamine
(a 3° amine) :

15. Carbonyl Compounds The carbonyl group is a carbon-oxygen double bond.
Carbonyl compounds include many classes of compounds.

16. Aldehydes and Ketones
contain a carbonyl (C=O) group

17. Carboxylic Acids
contain a carboxyl (-COOH) group

18. Carboxylic Esters
Ester: a derivative of a carboxylic acid in which the carboxyl hydrogen is replaced by a carbon group

19. Carboxylic Amide
Carboxylic amide, commonly referred to as an amide: a derivative of a carboxylic acid in which the -OH of the -COOH group is replaced by an amine
the six atoms of the amide functional group lie in a plane with bond angles of approximately 120°