In the reduction of alkynes using sodium in liquid ammonia, which of the species below is not thought to be an intermediate in the commonly accepted mechanism?

Question

Quizplus · Accepted Answer

The commonly accepted mechanism for reduction of alkynes using sodium in liquid ammonia involves the formation of a radical anion intermediate, which is then protonated to give the corresponding alkene. There is no place in this mechanism for the formation of a vinyl cation intermediate, making choice D the correct answer.

In the Reduction of Alkynes Using Sodium in Liquid Ammonia