Question

Question: Give the structure corresponding to each IUPAC name.

a. 2-bromobutanoic acid

b. 2,3-dimethylpentanoic acid

c. 3,3,4-trimethylheptanoic acid

d. 2-sec-butyl-4,4-diethylnonanoic acid

e. 3,4-diethylcyclohexanecarboxylic acid

f. 1-isopropylcyclobutanecarboxylic acid

Short answer

Answer

a.

2-bromobutanoic acid

b.

2,3-dimethylpentanoic acid

c.

3,3,4-trimethylheptanoic acid

d.

2-sec butyl-4,4-diethylnonanoic acid

e.

3,4-diethylcyclohexanoic acid

f.

1-isopropylcyclobutane carboxylic acid

Step-by-step solution

Step-by-Step Solution Step 1: Carboxylic acids

Organic compounds containing the -COOH group in their carbon chain are called carboxylic acid.

The hydrogen in the carboxyl group is more acidic than the hydrogen in alcohols.

The C-O bond and O-H bond in the C-OH bond is polar. Since oxygen is more electronegative than carbon or hydrogen, oxygen is more electron-rich.

Therefore, in a carboxy group, both the oxygen atoms are electron-rich while carboxy carbon and hydroxyl hydrogen are electron deficient.

Predicting structure of carboxylic acid

The IUPAC names of carboxylic acid end with the suffix ‘-oic acid’.

From the IUPAC name, find the number of carbon atoms in the parent chain of the carboxylic acid. It will be the name of alkane ending with ‘oic’.

The substituents on the parent chain will be added as prefixes before the name of the parent chain with its position.

Both the parent chain and substituents are considered to find the complete structure of the acid.

Structure of acid with given IUPAC names

a. The parent chain contains four carbon atoms. The parent chain contains a bromine substituent at the second position.

The structure can then be given as:

2-bromobutanoic acid

b. The parent chain contains five carbon atoms. The parent chain contains methyl groups on the second and third positions.

The structure can then be given as

2,3-dimethylpentanoic acid

c. The parent chain contains seven carbon atoms. The parent chain contains methyl groups at third and fourth positions.

The structure can then be given as:

3,3,4-trimethylheptanoic acid

d. The parent chain contains nine carbon atoms. The parent chain contains secondary butyl groups and ethyl groups at second and fourth positions, respectively.

The structure can then be given as:

2-sec butyl-4,4-diethylnonanoic acid

e. The parent chain is a cyclic compound containing six carbon atoms. The parent chain contains ethyl substituents at the third and fourth positions.

The structure can then be given as:

3,4-diethylcyclohexanoic acid

f. The parent chain is a cyclic compound containing four carbon atoms. The parent chain contains isopropyl substituent at the first position.

The structure can then be given as:

1-isopropylcyclobutane carboxylic acid