Question

Amongst the following, the major product of the given chemical reaction is

• A.
• B.
• C.
• D.

Answer 1

The Correct Option is A

The given chemical reaction involves the bromination of an alkene using bromine (\text{Br}_2) in the presence of methanol (\text{CH}_3\text{OH}) as a solvent. This is a typical example of electrophilic addition, where bromine adds to the double bond of the alkene.

Let’s analyze the reaction step-by-step:

1. First, the bromine molecule (\text{Br}_2) approaches the double bond. The electron-rich double bond attacks the bromine molecule, forming a cyclic bromonium ion intermediate.
2. The intermediate bromonium ion is positively charged and highly reactive. It is then attacked by the nucleophile present in the solution. In this case, methanol (\text{CH}_3\text{OH}) acts as the nucleophile.
3. The methanol attacks the more substituted carbon of the bromonium ion, opening the three-membered ring and resulting in the formation of a bromoether.

The major product is determined based on the Markovnikov’s rule, where the nucleophile (methanol) will attach to the more substituted carbon atom of the alkene.

Based on these steps, the major product of the reaction is the one where methanol attaches to the more substituted carbon, as explained in steps 2 and 3. This corresponds to the following option:

Thus, the correct answer is the structure shown above, which represents the formation of a bromoether with the methanol group attached according to the Markovnikov’s rule.