Organic Chemistry Nomenclature

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Organic Chemistry Nomenclature

• How to name compounds

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• Classify Carbons according to how many OTHER
  CARBONS they are attached to

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3
1
2
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Alkanes
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Branched AlkanesThe IUPAC Rules

• Identify the longest continuous chain. This
  becomes the parent chain
• Start counting from Carbon nearest (largest)
  substituent (branch)
• Name substituent ends with -yl, e.g., methyl-,
  ethyl-, etc.
• Name the compound alphabetically, and write the
  same way. (e.g., ethyl before methyl
• Identify the carbon to which the substituent is
  attached by number

Example Longest chain is 5 carbons, so parent
is PENTANE. A methyl group is attached at C2, so
the compound is called 2-methylpentane
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Branched Chains
More than one substituent This example has 2,
but they are the same.
How many of the SAME substituents? 2-di- 3-tri- 4-
tetra-
Name by finding substituent that appears FIRST in
PARENT CHAIN
2,3-dimethylpentane
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2,2,4,5-tetramethylheptane
2,4,5-trimethylheptane
7-ethyl-2,3-dimethyldecane
4-ethyl-3,6-dimethyloctane
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Haloalkanes

• F fluoro-
• Cl chloro-
• Br bromo-
• I iodo-

Trichloromethane
2-bromo-3-chlorobutane
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Cycloalkanes

• Cyclo__________

Cyclopropane
Cyclobutane
Cyclopentane
Cyclohexane