Question Detail
Question
In the addition of hydrogen bromide to alkynes, which of the following species is believed to be an intermediate?
Correct Answer
Option B is the correct answer.
Detailed Explanation
In the electrophilic addition of HBr to alkynes, the first step involves protonation of the triple bond to form a vinyl cation (alkenyl cation) intermediate. This is analogous to the carbocation intermediate in alkene addition.
Hint
What intermediate is formed in electrophilic addition to alkynes?