Organic Names Functional Group Structures Hydrocarbons compounds  Elmhurst College
Root Name Position Numbers  Inorganic Groups  Chemistry Department
Functional Group Names Carbon Branches Final Name  Virtual ChemBook


 Final Name

Put all of the steps together to write the final name.

1. Root name of longest continuous chain.
2. Identify functional group.
3. Number the carbons to identify the functional group position.
4. Identify the branches and positions.
5. Identify any inorganic groups and positions.

Example top left - Branched Alkane:

Longest chain = heptane
Branches = methyl at carbon 3, ethyl at carbon 4

Final Name = 3-methyl-4-ethylheptane

 Notes on Multiple Branches:

If several branches are present, assign EVERY one a position number. When two or more branches are identical, the prefixes di, tri, etc. may be used, but every branch must still have a position number. If the branches are different, name each one separately with appropriate position numbers.


Example lower left - Branched Pentene:

Longest chain = 5 carbons - pent-
Functional group = alkene, therefore = pentene
Position of double bond on carbon 1, therefore 1-pentene
At carbon 2 and 4 there are a total of three methyl groups

Final Name = 2,4,4-trimethyl-1-pentene

*Note: TWO position numbers are necessary since one methyl group could be on carbon number 2, 3, or 4,