Naming Organic Compounds

Alcohols

All alcohols contain the hydroxyl functional group, -O-H, attached to single bonded hydrocarbons (alkanes). Alcohol have the general formula R-OH where R represents any chain of carbon and hydrogen atoms.

The four most common alcohols are:

CH₃OH

methanol

CH₃CH₂OH

ethanol

CH₃CH₂CH₂OH

1-propanol

OH | CH₃CHCH₃

2-propanol

Alcohols use the same formats as alkanes. To name alcohols,

Determine the parent chain. The parent chain must be the longest that includes the carbon holding the OH group.
Number according to the end closest to the -OH group regardless of where alkyl substituents are.
The format is as follows: (location of branch)-(branch name)-(location of OH group)-(parent chain)
Change the parent chain -e ending and replace it with an -ol.

Example:

                       H
                       |
                 H H H-C-H H
                 | |   |   |
               H-C-C---C---C-H
                 | |   |   |
                 H O   H   H
                   |
                   H
             Parent chain: butane
       -OH group location: 2
   Substituents locations: 3-methyl
              Alkane name: 3-methylbutane
             Alcohol name: 3-methyl-2-butanol

Alchohols containing more than one hydroxyl group are also called polyalcohols. Polyalcohols are named similarly to alcohols, with the exception of the prefix di-, tri-, etc before the -ol ending.

Example:

   
        H H
        | |
      H-C-C-H  
        | | 
       OH OH
   
      1,2-ethanediol
   
   
        H H H
        | | | 
      H-C-C-C-H	
        | | | 
      OH OH OH
   
   
      1,2,3-propanetriol