Q.3. - Organic Chemistry

Question

Question: Give the IUPAC name for each compound.

a.

b.

c.

d.

Step-by-Step Solution

Answer

Answer

 

1. m-1,3-diisopropylbenzene
2. 1-sec-butyl-4-ethylbenzene
3. m-butylphenol
4. 2-bromo-5-chlorotoulene

Step 1: Rules for IUPAC nomenclature for compounds containing an aromatic ring

• For one substituent - the name of substituent followed by word benzene

 

• For two substituent - use prefix for position 

1,2 - ortho

1,3 - meta

1,4 - para

Name the substituent in alphabetical order (excluding prefix)

 

• For more than two substituents - the number the substituent to get the lowest numbers possible

 

• If the ring is derivative of monosubstituted benzene, then replace benzene with the common name.

Step 2: IUPAC name of the compound

a. Two isopropyl groups at 1st and 3rd position - meta

 

Therefore, the IUPAC name of the compound is:

m-1,3-diisopropylbenzene

 

b. Two groups at 1 and 4 position - para

 

Therefore, the IUPAC name of the compound is:

1-sec-butyl-4-ethylbenzene

 

c. Monosubstituted derivative of benzene.

Benzene ring with -OH group - common name ‘phenol’.

One substituent at 3rd position with respect to OH – meta.

 

Therefore, the IUPAC name of the compound is:

m-butyl-phenol

 

 d. Monosubstituted derivative of benzene.

Benzene ring with $-C{H}_3$  group - common name ‘toluene’.

The molecule is named as benzene derivative therefore $-C{H}_3$ group is numbered 1.

Therefore, the IUPAC name of the compound is:

2-bromo-5-chlorotoulene