91Ó°ÊÓ

A systematic way of naming organic compounds based on their chemical composition and structure is given by the IUPAC nomenclature. IUPAC nomenclature consists of three main parts which are root name, suffix and prefix. Suffix denotes the functional group present whereas the number and name of the substituents are denoted by the prefix. In general, the IUPAC name for an organic compound can be written in the form as shown below.

$\text{substituent} \text{number}-(\text{name} \text{of} \text{substituent)(root name)(suffix)}$

(a)

The structure of the compound can be drawn as:

Structure of Compound

In this organic compound, one hydroxy group $\text{(}-\text{OH)}$is present at the fifth carbon atom and the ketone functional group is attached to the third carbon atom.Therefore, the IUPAC name of the compound is $\text{5}-\text{hydroxyhexan}-\text{3}-\text{one}$and the common name is $\mathrm{\pm ð³Ù³ó²â\pm ôβ}-\mathrm{hydroxypropylketone}$.

(b)

The structure of the compound can be drawn as:

Structure of Compound

In this organic compound, one phenyl group $\left(\mathrm{Ph}\right)$is present at the third carbon atom and the aldehyde functional group is attached to the first carbon atom. Therefore, the IUPAC name of the compound is $\text{3}-\text{phenylbutanal}$and the common name is $\mathrm{β}-\mathrm{phenylbutyraldehyde}$.

(c)

The structure of the compound is given as:

Structure of Compound

The IUPAC name of the compound is$\text{(1R,2R)}-\text{2}-\text{methoxycyclohexane}-\text{1}-\text{carbaldehyde}$

(d)

The structure of the compound is given as:

Structure of Compound

In this organic compound, two methyl groups are present at the sixth carbon atom and the ketone functional group is attached to the first carbon atom. Also, two double bonds are present at the second and fourth carbon atoms respectively. Therefore, the IUPAC name of the compound is $6,6-\text{dimethylcyclohexa}-2,4-\text{dienone}$.