91Ó°ÊÓ

IUPAC (The international union of pure and applied chemistry) defines the rule for the naming of any organic compound in chemistry.

The IUPAC rules are as follows:

1. Find and name the longest continuous carbon chain.
2. Identify and name groups attached to this chain.
3. Number the chain consecutively, starting at the end nearest a substituent group.
4. Designate the location of each substituent group by an appropriate number and name.
5. Assemble the name, and listening groups in alphabetical order using the full name for example cyclopropyl should be named first and then isobutyl.

6. The prefixes, di, tri, tetra etc used to designate several groups of the same kind, are not considered when alphabetizing.

In the provided compound a, there are six carbon atoms in the long chain, so the name of the parent chain is hexane. Number the chain and see that the substituents get the lowest possible number. So, the phenyl group is at second carbon, a methyl group is at fifth carbon. Thus, the IUPAC name of the compound is as follows:

5-methyl-2-phenylhexane