Rank the following radicals in order of decreasing stability (most stable to least stable).

Question

Quizplus · Accepted Answer

First, let's determine the stability factors of each radical. The stability order of radicals is:
III > I > II > IV (in other words, benzyl > allyl > tertiary > primary)
III is the most stable radical because it is stabilized by resonance with adjacent pi bonds. I is second most stable because it is also stabilized by resonance, but only with a single adjacent pi bond. II is less stable because it is tertiary, but still more stable than IV, which is a primary radical.
Therefore, the correct order, from most stable to least stable, is III > II > I > IV. This matches with choice C.

Rank the Following Radicals in Order of Decreasing Stability (Most