Structure 3.2.5
IUPAC Nomenclature
The systematic set of rules used to name organic compounds uniquely.
The 3-Step Naming System
PrefixSubstituentschloro-, methyl-
StemLongest Chainmeth-, eth-, prop-
SuffixMain Functional Group-ol, -oic acid, -al
The Priority Algorithm
Number the chain so the highest priority group gets the lowest locant.
Priority Hierarchy (Highest to Lowest)
Carboxylic Acid
>Ester
>Amide
>Nitrile
>Aldehyde
>Ketone
>Alcohol
>Amine
>Alkene
>Halogen / Alkyl
Deep Think Concept
Examiner Trap: The 'Ghost' Carbon
When naming Nitriles () or Carboxylic Acids (), the carbon in the functional group counts as Carbon-1.
is Propanenitrile (3 Carbons), NOT Ethanenitrile.