secondary suffix describes the functional group of the compound . Table . Suffix for IUPAC Name Class of the Compound Functional group Suffix used Alcohol −OH -ol Aldehyde −CHO -al Ketone O || −C− -one Carboxylic acid −COOH -oic acid . .
IUPAC rules for naming organic compounds: Rule1: Identify the longest chain of carbon atoms to get the parent name (root word). Rule : Number the carbon atoms of the parent chain, beginning at the closest end of the substituent or functional group . These are called locant numbers . If both functional group and substituent are present, then the priority will be given to the functional group .
Rule : In case of alkenes and alkynes, locate the double bond or triple bond and use its locant number followed by a dash and a primary suffix. The carbon chain is numbered in such a way that the multiple bonds have the lowest possible locant number. Rule : If the compound contains functional group, locate it and use its locant number followed by a dash and a secondary suffix. Rule : When the primary and secondary suffixes are joined, the terminal ‘e’ of the primary suffix is removed.
Rule : Identify the substituent and use a number followed by a dash and a prefix to specify its location and identity. . . IUPAC Nomenclature of hydrocarbons – Solved examples Let us try to name, systematically, some of the linear and substituted hydrocarbons by following IUPAC rules: Example : CH -CH -CH -CH -CH Step : It is a five- carbon chain and hence the root word is ‘Pent’.
(Rule ) Step : All the bonds between carbon atoms are single bonds, and thus the suffix is ‘ane’. So, its name is Pent + ane = Pentane Example : CH | CH −CH−CH −CH −CH Step : The longest chain contains five carbon atoms and hence the root word is ‘Pent’. Step : There is a substituent. So, the carbon chain is numbered from the left end, which is closest to the