Question

The correct IUPAC name is:

A) Isopropyl benzene
B) Cumene
C) Phenylisopropyl
D) None of these

Answer 1

The method of naming organic compounds is known as the IUPAC (International Union for Pure and Applied Chemistry) nomenclature. IUPAC is a common naming system which enlists standard rules. In the given structure, a benzene ring is present. An isopropyl group is attached to the benzene ring.

Complete answer:
The given structure with all of its atoms is as follows:

We know that the given structure contains a benzene ring. Thus, it is an aromatic compound. The group ${{\text{H}}_{\text{3}}}{\text{C}} - {\text{CH}} - {\text{C}}{{\text{H}}_{\text{3}}}$ is the substituent which is aliphatic in nature. Thus, in the given structure an aliphatic substituent is attached to an aromatic ring.

The group ${{\text{H}}_{\text{3}}}{\text{C}} - {\text{CH}} - {\text{C}}{{\text{H}}_{\text{3}}}$ contains three carbon atoms and one hydrogen atom less than propane. Thus, the group ${{\text{H}}_{\text{3}}}{\text{C}} - {\text{CH}} - {\text{C}}{{\text{H}}_{\text{3}}}$ is known as an isopropyl group. In the given structure, an isopropyl group is attached to the benzene ring.

According to IUPAC nomenclature, while naming the aromatic compounds, we first write the name of the substituent group as a prefix. Thus, the name of the given compound is isopropyl benzene. Thus, the correct IUPAC name is isopropyl benzene.

Additional Information
Isopropyl benzene is an organic compound. It is an aromatic hydrocarbon with an aliphatic substitution. Isopropyl benzene is colourless liquid in appearance. It is highly flammable in nature.

Thus, the correct answer is option (A) isopropyl benzene.

Note: The common name of the given compound is cumene. But we are asked to write the IUPAC name of the compound which is isopropyl benzene and not cumene. Do not confuse between the common name and IUPAC name. Other names for the given compound are (propan-2-yl)benzene, (1-methylethyl)benzene, and cumol.