Naming Alcohols

a. Common names

Simple alcohols are often called by their common names which consists of the name of the alkyl group to which the –OH group is attached followed by the word ‘alcohol’.

 

For example,     

         

CH₃OH     CH₃CH₂OH     CH₃CHOH

Methyl alcohol     Ethyl alcohol     |

CH₃

Isopropyl alcohol

 

b. IUPAC names

In the IUPAC system, alcohols are named as alkanols and their names are derived from the parent alkane by replacing the ‘e’ from the parent hydrocarbon and adding the suffix ‘ol’. For example:

 

For a cyclic alcohol, the –ol ending is added to the parent cycloalkane. For example,

OH

|

Cyclohexanol

 

c. Glycols

Dialcohols or diols are called glycols. They are named as derivatives of the parent hydrocarbon with the –diol name ending added. The –OH groups are added as prefixes. For example:

 

Exercise

Give systematic names for the following compounds

    (i)     CH₃CH₂CH₂CHCH₂CH₃

| OH

 

 

 

1. CH₃CHCH₂OH

    CH₃     OH

    |     |

1. CH₃CHCH₂ CHCH₂CH₃