91Ó°ÊÓ

IUPACis the International Union of Pure and Applied Chemistry, the organization which has given a certain set of rules for the nomenclature of the organic compounds. Some of the rules are:

1. Select the longest chain with maximum number of carbon atoms as the parent chain.
2. The remaining groups are called as substituents.
3. Name the substituents alphabetically.
4. If there are more than one same substituent, use di, tri, tetra, etc.
5. The prefix for alkane is ane, alkene is ene, and alkyne is yne.

Do the numbering of the compounds by identifying the parent chain having maximum number of carbon atoms. Identify the substituents and then name the compound accordingly.

(a)

Compound (a)

Here, the parent chain will comprise of 6 carbon atoms and is an alkene. On carbon-2, there is an ethyl substituent. So, the IUPAC name of the compound is 2-ethylhex-1-ene.

(b)

Compound (b)

Here, the parent chain will comprise of 6 carbon atoms and is an alkene. On carbon-3, there is an ethyl substituent. So, the IUPAC name of the compound is 3-ethyl hex-3-ene.

(c)

Compound (c)

Here, the parent chain will comprise of 9 carbon atoms and is an alkene. On carbon-2 and carbon-6, there is a methyl substituent. So, the IUPAC name of the compound is 2,6-dimethyl non-1,3,5-triene.

(d)

Compound (d)

Here, the parent chain will comprise of 7 carbon atoms and is an alkene. On carbon-4, there is an ethyl substituent. So, the IUPAC name of the compound is 4-ethyl hept-3-ene.

(e)

Compound (e)

Here, the parent chain will comprise of 6 carbon atoms and is a cyclic alkene. On carbon-1, there is acyclopentyl substituent. So, the IUPAC name of the compound is 1-cyclopentyl cyclohex-1,3-diene.

(f)

Compound (f)

Here, the parent chain will comprise of 9 carbon atoms and is an alkene with 3 double bonds having the priority. On carbon-3, there is achloromethyl substituent and on carbon-6, there is bromo group as the substituent. So, the IUPAC name of the compound is 6-bromo-3-chloromethyl non-1,3,5-triene.