Question

Write the IUPAC name of the given compound:

Answer 1

Write the name of substituents with their positions and then write the name of the ring with the prefix cyclo. Select the parent chain and give minimum locants to the substituted attached to it.

Complete step by step answer:
The IUPAC rules for the naming of cyclic compounds are as follows:
Determine the longest carbon chain and determine the substituents attached to the chain.
If two same long chains are present then select the more substituted chain.
Give the numbering to the carbon atoms of the chains so all the substituents get the lowest numbering.
Arrange the substituents in alphabetical order with their position in the chain.
If the same substituent is present more than one, then add ‘di’ for two, ‘tri’ for three, and so on.
Determine the longest carbon chain as follows:
The longest carbon chain is of six carbon atoms. The alkene having six carbon atoms is known as hexene and the cyclic hexene is named with the prefix cyclo, so the name of cyclic alkene having six carbon is cyclohexene.
Determine the substituent as follows:
The cyclohexene has one hydroxy and two nitro groups.
The cyclohexene having a hydroxyl group is known as phenol.
The structure of phenol is as follows:

Give the numbering to the chain as follows:

So, the parent chain has two nitro groups at carbon-2 and carbon-5.

So, the IUPAC name of the compound is 2,5-dinitrophenol.

Note: The cyclohexene ring ${{\text{C}}_{\text{6}}}{{\text{H}}_{\text{5}}}$ is known as benzene. The ring has a hydroxyl group at carbon- 1 so the compound can be named as 1-hydroxy-2,5-dinitrocyclohexene or 1-hydroxy-2,5-dinitrobenzene. Particularly the benzene ring having a hydroxyl group is named phenol.