IUPAC system and IUPAC rules of naming alcohols

In the common system, alcohols are named as alkyl alcohols. The word alcohol is added after the name of the alkyl group to which the hydroxyl group is attached. For e.g., CH3OH is methyl alcohol.

In the IUPAC system, the names of saturated alcohols are derived from corresponding alkenes by replacing 'e' of alkenes by 'ol'

Some examples are shown below.


IUPAC name of n propyl alcohol

IUPAC name of n butyl alcohol

The numbering is done such that the carbon atom attached to the

-OH group gets the lowest number.

 IUPAC name of butanol

structure of methyl propane 2 ol

IUPAC name of dimethyl propanpol

IUPAC name of methylbutanol

For naming polyhydric alcohols, the name of the alkane is retained and the ending -e is not dropped. Thus dihydric alcohols are named as alkane diols and trihydric alcohols are named as alkene triols.

dihydric alcohols are named as alkane diols
propane 1 2 3 triol

The position of carbon atoms carrying -OH groups are indicated by locants written after the name of alkene. The number of hydroxyl groups is indicated by adding the multiplicative prefix di, tri, tetra etc., before the suffix-ol.

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