5-Chloro-1,3-cyclopentadiene (below) undergoes SN1 solvolysis in the presence of silver ion extremely slowly even though the chlorine

Question:

5-Chloro-1,3-cyclopentadiene (below) undergoes SN1 solvolysis in the presence of silver ion extremely slowly even though the chlorine is doubly allylic and allylic halides normally ionize readily (Section 15.15). Provide an explanation for this behavior.