Question

In the following given reaction, ' $A$ ' is

• A.
• B.
• C.
• D.

Answer 1

The Correct Option is D

To solve this question, we need to identify the major product 'A' formed from the reaction given below: 

The reaction involves the addition of HBr to an alkene. The key to determining the major product is to apply Markovnikov's rule. According to Markovnikov's rule, in the addition of HX (where X is a halogen) to an alkene, the hydrogen atom from HX will attach to the carbon atom with more hydrogen atoms, while the halogen (Br in this case) will attach to the carbon atom with fewer hydrogen atoms.

1. The given alkene is 2-methylcyclopropene.
2. When HBr is added, the double bond opens up, and the hydrogen atom from HBr will attach to the carbon with more hydrogen atoms (the terminal carbon of the double bond).
3. Thus, the bromine will attach to the more substituted carbon, resulting in 2-bromo-2-methylpropane as the major product.

Therefore, the correct answer is the option depicting 2-bromo-2-methylpropane.