From the following, choose the one which are not secondary haloalkanes:

A. 2-Bromobutane

B. 1-Bromo-3-methylbutane

C. 3-Bromopentane

D. 2-Bromo-2-methylpentane

E. 2-Bromo-3-methylbutane

Choose the correct answer from the options given below:

B and D only

The correct answer is option 1. B and D only.

The structure of the given compounds are:

To determine which compounds are not secondary haloalkanes, we need to understand the classification of haloalkanes based on the position of the halogen atom (in this case, bromine) relative to the carbon atoms in the chain.

Haloalkane Classification

Primary Haloalkane: The halogen is attached to a carbon atom that is bonded to only one other carbon.

Secondary Haloalkane: The halogen is attached to a carbon atom that is bonded to two other carbons.

Tertiary Haloalkane: The halogen is attached to a carbon atom that is bonded to three other carbons.

Analysis of Each Compound

A. 2-Bromobutane

The bromine is attached to the second carbon in a four-carbon chain (butane). This second carbon is bonded to two other carbons. This is a secondary haloalkane.

B. 1-Bromo-3-methylbutane

The bromine is attached to the first carbon in a five-carbon chain (butane). This first carbon is bonded to only one other carbon. This is a primary haloalkane.

C. 3-Bromopentane

The bromine is attached to the third carbon in a five-carbon chain (pentane). This third carbon is bonded to two other carbons. This is a secondary haloalkane.

D. 2-Bromo-2-methylpentane

The bromine is attached to the second carbon in a five-carbon chain, where this second carbon is also bonded to a methyl group. Therefore, this carbon is connected to three other carbons. This is a tertiary haloalkane.

E. 2-Bromo-3-methylbutane

The bromine is attached to the second carbon in a four-carbon chain with a methyl group attached to the third carbon. This second carbon is bonded to two other carbons. This is a secondary haloalkane.

Thus, the correct answer is 1: B and D only.