 The basic rules
 There are some general rules which you should remember when naming organic compounds:
 The longest unbranched chain containing the functional group is the parent molecule or simply the longest unbranched chain for alkanes. Remember that the longest chain can go round a bend.
 Indicate the position of the functional group with a number, numbering from the end nearest the functional group.
 Name the branches and indicate the number of branches.

 Indicate the position of the branches with a number, numbering from the end nearest the functional group.
If there is more than one branch, the branches are identified in alphabetical order ignoring any di, tri etc.
 Be aware!
Each branch needs to be numbered individually, even if they are attached to the same carbon atom.
The rule is a comma between numbers and a dash between numbers and letters.

 Alkanes
 The alkanes don't contain a functional group and so the branches are numbered from the end that gives the lowest set of position numbers for the branches.
Use the above rules to see how the names of the alkanes below are built up.

 Alkenes and alkynes
 The functional group in the alkenes is the carbon to carbon double bond.
The functional group in the alkynes is the carbon to carbon triple bond.
The basic rules of naming apply.
The position of the double or triple bond is indicated by a number before the -ene or -yne part of the name.

Naming alcohols, aldehydes and ketones
 Alcohols
 The functional group in the alcohols is the hydroxyl group (-OH).
Alcohols end in the letters -ol
The basic rules of naming apply.
The position of the hydroxyl functional group is indicated by a number before the -ol part of the name.

Naming alcohols, aldehydes and ketones
 Be aware!
Alcohols can also be termed primary, secondary or tertiary.
 Primary has the -OH on the end of a chain.
Secondary has the -OH on a non-branched carbon atom along the chain.
Tertiary has the -OH on a branched carbon atom along the chain.

Naming alcohols, aldehydes and ketones

Naming alcohols, aldehydes and ketones
 Aldehydes
 All aldehydes contain a carbonyl functional group. The carbonyl group will never have a position number in an aldehyde as it is always on the end of the carbon chain.
Aldehydes end in the letters -al .
The basic rules of naming apply.

Naming alcohols, aldehydes and ketones

Naming alcohols, aldehydes and ketones
 Ketones
 Ketones also contain a carbonyl functional group but in ketones it is never on the end of a carbon chain.
Ketones end in the letters -one .
The naming rules in part 1 apply as before.

Naming alcohols, aldehydes and ketones

Naming carboxilic acids and esters
 Carboxylic acids contain the carboxyl functional group (-COOH) The carboxyl group will never have a position number in a carboxylic acid as it is always on the end of the carbon chain.
Carboxylic acids end in -oic acid.
The basic rules of naming apply.

Naming carboxilic acids and esters

Naming carboxilic acids and esters
 An ester is made from an alcohol and a carboxylic acid.
Esters have their own rules for naming.
The first part of the name comes from the alcohol and it ends with the letters -yl .
The second part of the name comes from the carboxylic acid and it ends with the letters oate .

Naming carboxilic acids and esters
Name of
Alcohol
Ethanol
Butanol
Pentanol
Name of
Carboxylic acid propanoic acid methanoic acid
Name of ester ethyl propanoate butyl methanoate ethanoic acid pentyl ethanoate